A324398 -id:A324398 - cp's OEIS frontend

A324874 a(n) is the binary length of A324398(n), where A324398(n) = A156552(n) AND (A323243(n) - A156552(n)).

0, 0, 0, 1, 0, 1, 0, 1, 3, 0, 0, 1, 0, 1, 4, 4, 0, 1, 0, 1, 5, 1, 0, 1, 0, 1, 4, 1, 0, 1, 0, 1, 0, 1, 5, 4, 0, 1, 7, 1, 0, 1, 0, 1, 3, 1, 0, 1, 0, 0, 2, 1, 0, 1, 6, 1, 9, 1, 0, 1, 0, 1, 3, 6, 0, 1, 0, 1, 0, 1, 0, 5, 0, 1, 5, 1, 6, 1, 0, 1, 4, 1, 0, 1, 8, 1, 11, 1, 0, 6, 7, 1, 0, 1, 9, 5, 0, 0, 7, 5, 0, 1, 0, 1, 6

Offset: 1

Antti Karttunen, Mar 27 2019

nonn

Antti Karttunen, Table of n, a(n) for n = 1..10000 (based on Hans Havermann's factorization of A156552)
Index entries for sequences related to binary expansion of n
Index entries for sequences computed from indices in prime factorization
Index entries for sequences related to sigma(n)

Cf. A000523, A070939, A156552, A323243, A324398, A324862, A324864, A324868, A324881.

A156552(n) = {my(f = factor(n), p2 = 1, res = 0); for(i = 1, #f~, p = 1 << (primepi(f[i, 1]) - 1); res += (p * p2 * (2^(f[i, 2]) - 1)); p2 <<= f[i, 2]); res}; \\ From A156552
A324398(n) = { my(k=A156552(n)); bitand(k,(A323243(n)-k)); }; \\ Needs also code from A323243.
A324874(n) = #binary(A324398(n));

If A324398(n) = 0, a(n) = 0, otherwise a(n) = A070939(A324398(n)) = 1 + A000523(A324398(n)).
a(n) = A324868(n) + A324881(n).
a(p) = 0 for all primes p.

A324868 Binary weight of A324398(n).

Original entry on oeis.org

0, 0, 0, 1, 0, 1, 0, 1, 2, 0, 0, 1, 0, 1, 1, 2, 0, 1, 0, 1, 1, 1, 0, 1, 0, 1, 2, 1, 0, 1, 0, 1, 0, 1, 2, 2, 0, 1, 2, 1, 0, 1, 0, 1, 2, 1, 0, 1, 0, 0, 1, 1, 0, 1, 2, 1, 2, 1, 0, 1, 0, 1, 2, 3, 0, 1, 0, 1, 0, 1, 0, 2, 0, 1, 1, 1, 1, 1, 0, 1, 2, 1, 0, 1, 2, 1, 2, 1, 0, 2, 2, 1, 0, 1, 1, 3, 0, 0, 2, 2, 0, 1, 0, 1, 2

Offset: 1

Antti Karttunen, Mar 18 2019

nonn

Antti Karttunen, Table of n, a(n) for n = 1..10000 (based on Hans Havermann's factorization of A156552)
Index entries for sequences related to binary expansion of n
Index entries for sequences computed from indices in prime factorization
Index entries for sequences related to sigma(n)

Cf. A000120, A156552, A323243, A324398, A324816.

A156552(n) = {my(f = factor(n), p2 = 1, res = 0); for(i = 1, #f~, p = 1 << (primepi(f[i, 1]) - 1); res += (p * p2 * (2^(f[i, 2]) - 1)); p2 <<= f[i, 2]); res}; \\ From A156552
A324398(n) = { my(k=A156552(n)); bitand(k,(A323243(n)-k)); }; \\ Needs also code from A323243.
A324868(n) = hammingweight(A324398(n));

a(n) = A000120(A324398(n)).

A324878 Xor-Moebius transform of A324398, where A324398(n) = A156552(n) AND (A323243(n) - A156552(n)).

Original entry on oeis.org

0, 0, 0, 1, 0, 1, 0, 0, 6, 0, 0, 1, 0, 1, 8, 8, 0, 6, 0, 0, 16, 1, 0, 0, 0, 1, 12, 1, 0, 8, 0, 8, 0, 1, 20, 8, 0, 1, 66, 0, 0, 17, 0, 1, 8, 1, 0, 8, 0, 0, 2, 1, 0, 12, 36, 0, 258, 1, 0, 0, 0, 1, 16, 40, 0, 1, 0, 1, 0, 20, 0, 24, 0, 1, 24, 1, 32, 67, 0, 8, 0, 1, 0, 1, 132, 1, 1026, 0, 0, 40, 72, 1, 0, 1, 256, 16, 0, 1, 68, 16, 0, 3, 0, 0, 46

Offset: 1

Antti Karttunen, Mar 18 2019

nonn

Antti Karttunen, Table of n, a(n) for n = 1..10000 (based on Hans Havermann's factorization of A156552)
Index entries for sequences related to binary expansion of n
Index entries for sequences computed from indices in prime factorization
Index entries for sequences related to sigma(n)

Cf. A156552, A318458, A324820, A324821, A324876, A324877.

A156552(n) = {my(f = factor(n), p2 = 1, res = 0); for(i = 1, #f~, p = 1 << (primepi(f[i, 1]) - 1); res += (p * p2 * (2^(f[i, 2]) - 1)); p2 <<= f[i, 2]); res}; \\ From A156552
A318458(n) = bitand(n, sigma(n)-n);
A324398(n) = if(1==n,0,A318458(A156552(n)));
\\ Or, equivalently:
A324398(n) = { my(k=A156552(n)); bitand(k,(A323243(n)-k)); }; \\ Needs also code from A323243.
A324878(n) = { my(v=0); fordiv(n, d, if(issquarefree(n/d), v=bitxor(v, A324398(d)))); (v); };

a(p) = 0 for all primes p.

A324881 Number of nonleading zeros in binary representation of A324398, where A324398(n) = A156552(n) AND (A323243(n) - A156552(n)).

Original entry on oeis.org

0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 3, 2, 0, 0, 0, 0, 4, 0, 0, 0, 0, 0, 2, 0, 0, 0, 0, 0, 0, 0, 3, 2, 0, 0, 5, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 4, 0, 7, 0, 0, 0, 0, 0, 1, 3, 0, 0, 0, 0, 0, 0, 0, 3, 0, 0, 4, 0, 5, 0, 0, 0, 2, 0, 0, 0, 6, 0, 9, 0, 0, 4, 5, 0, 0, 0, 8, 2, 0, 0, 5, 3, 0, 0, 0, 0, 4

Offset: 1

Antti Karttunen, Mar 27 2019

nonn

			For n=4, A324398(4) = 1, in binary "1", thus a(4) = 0.
For n=9, A324398(9) = 6, in binary "110", thus a(9) = 1.
For n=16, A324398(16) = 9, in binary "1001", thus a(16) = 2.

Antti Karttunen, Table of n, a(n) for n = 1..10000 (based on Hans Havermann's factorization of A156552)
Index entries for sequences related to binary expansion of n
Index entries for sequences computed from indices in prime factorization
Index entries for sequences related to sigma(n)

Cf. A080791, A156552, A323243, A324398, A324868, A324874.

PARI
```
A324881(n) = (A324874(n)-A324868(n));
```

a(n) = A080791(A324398(n)) = A324874(n) - A324868(n).

a(p) = 0 for all primes p.

A156552 Unary-encoded compressed factorization of natural numbers.

Original entry on oeis.org

0, 1, 2, 3, 4, 5, 8, 7, 6, 9, 16, 11, 32, 17, 10, 15, 64, 13, 128, 19, 18, 33, 256, 23, 12, 65, 14, 35, 512, 21, 1024, 31, 34, 129, 20, 27, 2048, 257, 66, 39, 4096, 37, 8192, 67, 22, 513, 16384, 47, 24, 25, 130, 131, 32768, 29, 36, 71, 258, 1025, 65536, 43, 131072, 2049, 38, 63, 68, 69, 262144

Offset: 1

Leonid Broukhis, Feb 09 2009

The primes become the powers of 2 (2 -> 1, 3 -> 2, 5 -> 4, 7 -> 8); the composite numbers are formed by taking the values for the factors in the increasing order, multiplying them by the consecutive powers of 2, and summing. See the Example section.
From Antti Karttunen, Jun 27 2014: (Start)
The odd bisection (containing even terms) halved gives A244153.
The even bisection (containing odd terms), when one is subtracted from each and halved, gives this sequence back.
(End)
Question: Are there any other solutions that would satisfy the recurrence r(1) = 0; and for n > 1, r(n) = Sum_{d|n, d>1} 2^A033265(r(d)), apart from simple variants 2^k * A156552(n)? See also A297112, A297113. - Antti Karttunen, Dec 30 2017

			For 84 = 2*2*3*7 -> 1*1 + 1*2 + 2*4 + 8*8 =  75.
For 105 = 3*5*7 -> 2*1 + 4*2 + 8*4 = 42.
For 137 = p_33 -> 2^32 = 4294967296.
For 420 = 2*2*3*5*7 -> 1*1 + 1*2 + 2*4 + 4*8 + 8*16 = 171.
For 147 = 3*7*7 = p_2 * p_4 * p_4 -> 2*1 + 8*2 + 8*4 = 50.

David A. Corneth, Table of n, a(n) for n = 1..10000 (first 1024 terms from Antti Karttunen)
Hans Havermann, Factorization of the first 10000 terms, in format [[primes], [exponents]]
A puzzle by Sergey Orlov (in Russian)
Index entries for sequences related to binary expansion of n
Index entries for sequences that are permutations of the natural numbers
Index entries for sequences computed from indices in prime factorization

One less than A005941.
Inverse permutation: A005940 with starting offset 0 instead of 1.
Cf. A000079, A000120, A001222, A052126, A054429, A061395, A064216, A064989, A003188, A243071, A243065-A243066, A244153, A243354, A112798, A125106, A056239, A161511.
Cf. also A297106, A297112 (Möbius transform), A297113, A153013, A290308, A300827, A323243, A323244, A323247, A324201, A324812 (n for which a(n) is a square), A324813, A324822, A324823, A324398, A324713, A324815, A324819, A324865, A324866, A324867.
Other related permutations: A253551, A253792, A253564, A253791, A277195, A297163, A297164, A297165, A297166, A302023, A305418, A322863, A322864.

Table[Floor@ Total@ Flatten@ MapIndexed[#1 2^(#2 - 1) &, Flatten[ Table[2^(PrimePi@ #1 - 1), {#2}] & @@@ FactorInteger@ n]], {n, 67}] (* Michael De Vlieger, Sep 08 2016 *)

a(n) = {my(f = factor(n), p2 = 1, res = 0); for(i = 1, #f~, p = 1 << (primepi(f[i, 1]) - 1); res += (p * p2 * (2^(f[i, 2]) - 1)); p2 <<= f[i, 2]); res}; \\ David A. Corneth, Mar 08 2019

A064989(n) = {my(f); f = factor(n); if((n>1 && f[1,1]==2), f[1,2] = 0); for (i=1, #f~, f[i,1] = precprime(f[i,1]-1)); factorback(f)};
A156552(n) = if(1==n, 0, if(!(n%2), 1+(2*A156552(n/2)), 2*A156552(A064989(n)))); \\ (based on the given recurrence) - Antti Karttunen, Mar 08 2019

# Program corrected per instructions from Leonid Broukhis. - Antti Karttunen, Jun 26 2014
# However, it gives correct answers only up to n=136, before corruption by a wrap-around effect.
# Note that the correct answer for n=137 is A156552(137) = 4294967296.
$max = $ARGV[0];
$pow = 0;
foreach $i (2..$max) {
@a = split(/ /, `factor $i`);
shift @a;
$shift = 0;
$cur = 0;
while ($n = int shift @a) {
$prime{$n} = 1 << $pow++ if !defined($prime{$n});
$cur |= $prime{$n} << $shift++;
}
print "$cur, ";
}
print "\n";
(Scheme, with memoization-macro definec from Antti Karttunen's IntSeq-library, two different implementations)
(definec (A156552 n) (cond ((= n 1) 0) (else (+ (A000079 (+ -2 (A001222 n) (A061395 n))) (A156552 (A052126 n))))))
(definec (A156552 n) (cond ((= 1 n) (- n 1)) ((even? n) (+ 1 (* 2 (A156552 (/ n 2))))) (else (* 2 (A156552 (A064989 n))))))
;; Antti Karttunen, Jun 26 2014

from sympy import primepi, factorint
def A156552(n): return sum((1<Chai Wah Wu, Mar 10 2023

From Antti Karttunen, Jun 26 2014: (Start)
a(1) = 0, a(n) = A000079(A001222(n)+A061395(n)-2) + a(A052126(n)).
a(1) = 0, a(2n) = 1+2*a(n), a(2n+1) = 2*a(A064989(2n+1)). [Compare to the entanglement recurrence A243071].
For n >= 0, a(2n+1) = 2*A244153(n+1). [Follows from the latter clause of the above formula.]
a(n) = A005941(n) - 1.
As a composition of related permutations:
a(n) = A003188(A243354(n)).
a(n) = A054429(A243071(n)).
For all n >= 1, A005940(1+a(n)) = n and for all n >= 0, a(A005940(n+1)) = n. [The offset-0 version of A005940 works as an inverse for this permutation.]
This permutations also maps between the partition-lists A112798 and A125106:
A056239(n) = A161511(a(n)). [The sums of parts of each partition (the total sizes).]
A003963(n) = A243499(a(n)). [And also the products of those parts.]
(End)
From Antti Karttunen, Oct 09 2016: (Start)
A161511(a(n)) = A056239(n).
A029837(1+a(n)) = A252464(n). [Binary width of terms.]
A080791(a(n)) = A252735(n). [Number of nonleading 0-bits.]
A000120(a(n)) = A001222(n). [Binary weight.]
For all n >= 2, A001511(a(n)) = A055396(n).
For all n >= 2, A000120(a(n))-1 = A252736(n). [Binary weight minus one.]
A252750(a(n)) = A252748(n).
a(A250246(n)) = A252754(n).
a(A005117(n)) = A277010(n). [Maps squarefree numbers to a permutation of A003714, fibbinary numbers.]
A085357(a(n)) = A008966(n). [Ditto for their characteristic functions.]
For all n >= 0:
a(A276076(n)) = A277012(n).
a(A276086(n)) = A277022(n).
a(A260443(n)) = A277020(n).
(End)
From Antti Karttunen, Dec 30 2017: (Start)
For n > 1, a(n) = Sum_{d|n, d>1} 2^A033265(a(d)). [See comments.]
More linking formulas:
A106737(a(n)) = A000005(n).
A290077(a(n)) = A000010(n).
A069010(a(n)) = A001221(n).
A136277(a(n)) = A181591(n).
A132971(a(n)) = A008683(n).
A106400(a(n)) = A008836(n).
A268411(a(n)) = A092248(n).
A037011(a(n)) = A010052(n) [conjectured, depends on the exact definition of A037011].
A278161(a(n)) = A046951(n).
A001316(a(n)) = A061142(n).
A277561(a(n)) = A034444(n).
A286575(a(n)) = A037445(n).
A246029(a(n)) = A181819(n).
A278159(a(n)) = A124859(n).
A246660(a(n)) = A112624(n).
A246596(a(n)) = A069739(n).
A295896(a(n)) = A053866(n).
A295875(a(n)) = A295297(n).
A284569(a(n)) = A072411(n).
A286574(a(n)) = A064547(n).
A048735(a(n)) = A292380(n).
A292272(a(n)) = A292382(n).
A244154(a(n)) = A048673(n), a(A064216(n)) = A244153(n).
A279344(a(n)) = A279339(n), a(A279338(n)) = A279343(n).
a(A277324(n)) = A277189(n).
A037800(a(n)) = A297155(n).
For n > 1, A033265(a(n)) = 1+A297113(n).
(End)
From Antti Karttunen, Mar 08 2019: (Start)
a(n) = A048675(n) + A323905(n).
a(A324201(n)) = A000396(n), provided there are no odd perfect numbers.
The following sequences are derived from or related to the base-2 expansion of a(n):
A000265(a(n)) = A322993(n).
A002487(a(n)) = A323902(n).
A005187(a(n)) = A323247(n).
A324288(a(n)) = A324116(n).
A323505(a(n)) = A323508(n).
A079559(a(n)) = A323512(n).
A085405(a(n)) = A323239(n).
The following sequences are obtained by applying to a(n) a function that depends on the prime factorization of its argument, which goes "against the grain" because a(n) is the binary code of the factorization of n, which in these cases is then factored again:
A000203(a(n)) = A323243(n).
A033879(a(n)) = A323244(n) = 2*a(n) - A323243(n),
A294898(a(n)) = A323248(n).
A000005(a(n)) = A324105(n).
A000010(a(n)) = A324104(n).
A083254(a(n)) = A324103(n).
A001227(a(n)) = A324117(n).
A000593(a(n)) = A324118(n).
A001221(a(n)) = A324119(n).
A009194(a(n)) = A324396(n).
A318458(a(n)) = A324398(n).
A192895(a(n)) = A324100(n).
A106315(a(n)) = A324051(n).
A010052(a(n)) = A324822(n).
A053866(a(n)) = A324823(n).
A001065(a(n)) = A324865(n) = A323243(n) - a(n),
A318456(a(n)) = A324866(n) = A324865(n) OR a(n),
A318457(a(n)) = A324867(n) = A324865(n) XOR a(n),
A318458(a(n)) = A324398(n) = A324865(n) AND a(n),
A318466(a(n)) = A324819(n) = A323243(n) OR 2*a(n),
A318467(a(n)) = A324713(n) = A323243(n) XOR 2*a(n),
A318468(a(n)) = A324815(n) = A323243(n) AND 2*a(n).
(End)

More terms from Antti Karttunen, Jun 28 2014

A323244 a(1) = 0; and for n > 1, a(n) = A033879(A156552(n)).

Original entry on oeis.org

0, 1, 1, 2, 1, 4, 1, 6, 0, 5, 1, 10, 1, 16, 2, 6, 1, 12, 1, 18, -3, 18, 1, 22, -4, 46, 4, 22, 1, 10, 1, 30, 14, 82, -2, 14, 1, 256, -12, 22, 1, 36, 1, 66, 8, 226, 1, 46, -12, 19, 8, 130, 1, 28, -19, 70, -12, 748, 1, 42, 1, 1362, 16, 22, 10, 42, 1, 214, 254, 40, 1, 38, 1, 3838, 10, 406, -10, 106, 1, 78, -12, 5458, 1, 26, -72, 12250, -348, 30, 1, 12

Offset: 1

Antti Karttunen, Jan 10 2019

sign

After a(1) = 0, the other zeros occur for k >= 1, at A005940(1+A000396(k)), which, provided no odd perfect numbers exist, is equal to A324201(k) = A062457(A000043(k)): 9, 125, 161051, 410338673, ..., etc.

There are 2321 negative terms among the first 10000 terms.

Antti Karttunen, Table of n, a(n) for n = 1..10000 (based on Hans Havermann's factorization of A156552)
Index entries for sequences related to binary expansion of n
Index entries for sequences computed from indices in prime factorization
Index entries for sequences related to sigma(n)

Cf. A000043, A000396, A033879, A064989, A156552, A297112, A323240, A323243, A323245, A323248, A324115, A324051, A324103, A324396, A324398, A324543, A324713.
Cf. A324201 (positions of zeros, conjectured), A324551 (of negative terms), A324720 (of nonnegative terms), A324721 (of positive terms), A324731, A324732.
Cf. A329644 (Möbius transform).
Cf. A323174, A324055, A324185, A324546 for other permutations of deficiency, and also A324574, A324575, A324654.

Array[2 # - If[# == 0, 0, DivisorSigma[1, #]] &@ Floor@ Total@ Flatten@ MapIndexed[#1 2^(#2 - 1) &, Flatten[Table[2^(PrimePi@ #1 - 1), {#2}] & @@@ FactorInteger@ #]] &, 90] (* Michael De Vlieger, Apr 21 2019 *)

A064989(n) = {my(f); f = factor(n); if((n>1 && f[1,1]==2), f[1,2] = 0); for (i=1, #f~, f[i,1] = precprime(f[i,1]-1)); factorback(f)};
A156552(n) = if(1==n, 0, if(!(n%2), 1+(2*A156552(n/2)), 2*A156552(A064989(n))));
A323244(n) = if(1==n, 0, my(k=A156552(n)); (2*k)-sigma(k));

from sympy import divisor_sigma, primepi, factorint
def A323244(n): return (lambda n: (n<<1)-divisor_sigma(n))(sum((1< 1 else 0 # Chai Wah Wu, Mar 10 2023

a(n) = 2*A156552(n) - A323243(n).
a(1) = 0; and for n > 1, a(n) = A033879(A156552(n)).
a(n) = A323248(n) + A001222(n) = (A323247(n) - A323243(n)) + A001222(n).
From Antti Karttunen, Mar 12 2019 & Nov 23 2019: (Start)
a(n) = Sum_{d|n} (2*A297112(d) - A324543(d)) = Sum_{d|n} A329644(d).
A002487(a(n)) = A324115(n).
a(n) = A329638(n) - A329639(n).
a(n) = A329645(n) - A329646(n).
(End)

A324866 a(n) = A156552(n) OR A324865(n), where OR is bitwise-OR, A003986.

Original entry on oeis.org

0, 1, 3, 3, 7, 5, 15, 7, 6, 13, 31, 11, 63, 17, 10, 15, 127, 13, 255, 19, 23, 47, 511, 23, 28, 83, 14, 47, 1023, 31, 2047, 31, 54, 175, 22, 31, 4095, 257, 78, 55, 8191, 37, 16383, 67, 30, 799, 32767, 47, 60, 31, 250, 131, 65535, 29, 55, 71, 270, 1301, 131071, 43, 262143, 2735, 54, 63, 126, 95, 524287, 303, 774, 41, 1048575, 55

Offset: 1

Antti Karttunen, Mar 18 2019

nonn

Antti Karttunen, Table of n, a(n) for n = 1..10000 (based on Hans Havermann's factorization of A156552)
Index entries for sequences related to binary expansion of n
Index entries for sequences computed from indices in prime factorization
Index entries for sequences related to sigma(n)

Cf. A001065, A003986, A156552, A318456, A323243, A324865, A324867, A324398, A324876.

A156552(n) = {my(f = factor(n), p2 = 1, res = 0); for(i = 1, #f~, p = 1 << (primepi(f[i, 1]) - 1); res += (p * p2 * (2^(f[i, 2]) - 1)); p2 <<= f[i, 2]); res}; \\ From A156552
A318456(n) = bitor(n,sigma(n)-n);
A324866(n) = if(1==n,0,A318456(A156552(n)));

A324866(n) = { my(k=A156552(n)); bitor(k,(A323243(n)-k)); }; \\ Needs also code from A323243.

a(1) = 0; for n > 1, a(n) = A318456(A156552(n)).

a(n) = A156552(n) OR (A323243(n) - A156552(n)).

A324396 a(1) = 0; for n > 1, a(n) = A009194(A156552(n)).

Original entry on oeis.org

0, 1, 1, 1, 1, 1, 1, 1, 6, 1, 1, 1, 1, 1, 2, 3, 1, 1, 1, 1, 3, 3, 1, 1, 4, 1, 2, 1, 1, 1, 1, 1, 2, 1, 2, 1, 1, 1, 6, 1, 1, 1, 1, 1, 2, 1, 1, 1, 12, 1, 2, 1, 1, 1, 1, 1, 6, 1, 1, 1, 1, 3, 2, 1, 2, 3, 1, 1, 2, 1, 1, 1, 1, 1, 2, 1, 10, 1, 1, 1, 6, 1, 1, 1, 12, 5, 6, 15, 1, 3, 3, 1, 2, 3, 4, 5, 1, 1, 2, 3, 1, 3, 1, 1, 6

Offset: 1

Antti Karttunen, Mar 05 2019

nonn

Cf. A009194, A156552, A323243, A323244, A324051, A324394, A324397, A324398.

A009194(n) = gcd(n, sigma(n));
A064989(n) = {my(f); f = factor(n); if((n>1 && f[1,1]==2), f[1,2] = 0); for (i=1, #f~, f[i,1] = precprime(f[i,1]-1)); factorback(f)};
A156552(n) = if(1==n, 0, if(!(n%2), 1+(2*A156552(n/2)), 2*A156552(A064989(n))));
A324396(n) = if(1==n,0,A009194(A156552(n)));

a(1) = 0; for n > 1, a(n) = A009194(A156552(n)).

a(n) = gcd(A156552(n), A323243(n)).

A324867 a(n) = A156552(n) XOR A324865(n), where XOR is bitwise-xor, A003987.

Original entry on oeis.org

0, 1, 3, 2, 7, 4, 15, 6, 0, 13, 31, 10, 63, 16, 2, 6, 127, 12, 255, 18, 7, 46, 511, 22, 28, 82, 4, 46, 1023, 30, 2047, 30, 54, 174, 2, 22, 4095, 256, 12, 54, 8191, 36, 16383, 66, 24, 798, 32767, 46, 60, 31, 248, 130, 65535, 28, 19, 70, 12, 1300, 131071, 42, 262143, 2734, 48, 22, 126, 94, 524287, 302, 774, 40, 1048575, 38, 2097151, 4354, 10

Offset: 1

Antti Karttunen, Mar 18 2019

nonn

Antti Karttunen, Table of n, a(n) for n = 1..10000 (based on Hans Havermann's factorization of A156552)
Index entries for sequences related to binary expansion of n
Index entries for sequences computed from indices in prime factorization
Index entries for sequences related to sigma(n)

Cf. A001065, A003986, A156552, A318457, A323243, A324865, A324866, A324398, A324877.

A156552(n) = {my(f = factor(n), p2 = 1, res = 0); for(i = 1, #f~, p = 1 << (primepi(f[i, 1]) - 1); res += (p * p2 * (2^(f[i, 2]) - 1)); p2 <<= f[i, 2]); res}; \\ From A156552
A318457(n) = bitxor(n,sigma(n)-n);
A324867(n) = if(1==n,0,A318457(A156552(n)));

A324867(n) = { my(k=A156552(n)); bitxor(k,(A323243(n)-k)); }; \\ Needs also code from A323243.

a(1) = 0; for n > 1, a(n) = A318457(A156552(n)).
a(n) = A156552(n) XOR (A323243(n) - A156552(n)).
a(n) = A323243(n) - 2*A324398(n).

A324397 a(1) = 0; for n > 1, a(n) = A297114(A156552(n)).

Original entry on oeis.org

0, 0, 0, 0, 0, 2, 0, 3, -2, 3, 0, 7, 0, 14, -2, 0, 0, 9, 0, 15, -6, 9, 0, 18, -4, 33, -2, 14, 0, 4, 0, 25, -2, 42, -4, 7, 0, 254, -26, 9, 0, 33, 0, 63, -2, 140, 0, 41, -8, 14, -34, 127, 0, 24, -12, 66, -90, 579, 0, 38, 0, 684, -2, 6, -4, 21, 0, 175, -2, 37, 0, 24, 0, 3587, -2, 304, -8, 85, 0, 73, -14, 2733, 0, 6, -52, 8707, -378, 11, 0, 3

Offset: 1

Antti Karttunen, Mar 05 2019

sign

Antti Karttunen, Table of n, a(n) for n = 1..4137

Cf. A000203, A005187, A156552, A297114, A323243, A323244, A324103, A323247, A323248, A324396, A324398, A324542.

Array[If[# == 1, 0, Function[n, DivisorSum[n, MoebiusMu[n/#] (2 # - DigitCount[2 #, 2, 1] - DivisorSigma[1, #]) &]]@ Floor@ Total@ Flatten@ MapIndexed[#1 2^(#2 - 1) &, Flatten[Table[2^(PrimePi@ #1 - 1), {#2}] & @@@ FactorInteger@ #]]] &, 90] (* Michael De Vlieger, Mar 11 2019 *)

A064989(n) = {my(f); f = factor(n); if((n>1 && f[1,1]==2), f[1,2] = 0); for (i=1, #f~, f[i,1] = precprime(f[i,1]-1)); factorback(f)};
A156552(n) = if(1==n, 0, if(!(n%2), 1+(2*A156552(n/2)), 2*A156552(A064989(n))));
A005187(n) = { my(s=n); while(n>>=1, s+=n); s; };
\\ Slow: A297114(n) = sumdiv(n,d,moebius(n/d)*(A005187(d)-sigma(d)));
A297111(n) = sumdiv(n,d,moebius(n/d)*A005187(d));
A297114(n) = (A297111(n) - n);
A324397(n) = if(1==n,0,A297114(A156552(n)));

a(1) = 0; for n > 1, a(n) = A297114(A156552(n)).

For all n >= 1, a(2n-1) = A324103(2n-1).

cp's OEIS Frontend

A324874 a(n) is the binary length of A324398(n), where A324398(n) = A156552(n) AND (A323243(n) - A156552(n)).

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A324868 Binary weight of A324398(n).

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A324878 Xor-Moebius transform of A324398, where A324398(n) = A156552(n) AND (A323243(n) - A156552(n)).

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A324881 Number of nonleading zeros in binary representation of A324398, where A324398(n) = A156552(n) AND (A323243(n) - A156552(n)).

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A156552 Unary-encoded compressed factorization of natural numbers.

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A323244 a(1) = 0; and for n > 1, a(n) = A033879(A156552(n)).

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A324866 a(n) = A156552(n) OR A324865(n), where OR is bitwise-OR, A003986.

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A324396 a(1) = 0; for n > 1, a(n) = A009194(A156552(n)).

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