cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

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A364494 Numbers k such that k divides A163511(k).

Original entry on oeis.org

1, 2, 3, 4, 6, 8, 9, 12, 16, 18, 24, 32, 36, 48, 64, 72, 96, 105, 128, 144, 192, 210, 256, 288, 384, 420, 429, 512, 576, 768, 840, 858, 1024, 1152, 1365, 1536, 1617, 1680, 1716, 2048, 2304, 2730, 3072, 3234, 3360, 3432, 3887, 4096, 4235, 4608, 5460, 6144, 6468, 6720, 6864, 7774, 8192, 8470, 9216, 10829, 10920, 12288
Offset: 1

Views

Author

Antti Karttunen, Jul 27 2023

Keywords

Comments

If n is present, then 2*n is also present, and vice versa.
A007283 is included as a subsequence, because it gives the known fixed points of map n -> A163511(n).

Crossrefs

Positions of 1's in A364491.
Cf. A163511.
Subsequences: A007283, A029744, A364495 (odd terms).
Cf. also A364295, A364496, A364497.

Programs

A364496 Numbers k such that k is a multiple of A163511(k).

Original entry on oeis.org

0, 3, 6, 12, 24, 48, 96, 192, 384, 768, 1536, 3072, 6144, 12288, 16383, 24576, 32766, 49152, 65532, 98304, 131064, 196608, 262128, 393216, 524256, 786432, 1048512, 1572864, 2097024, 3145728, 4194048, 6291456, 8388096, 12582912, 16776192, 25165824, 33552384, 50331648, 67104768, 100663296, 134209536, 201326592
Offset: 1

Views

Author

Antti Karttunen, Jul 27 2023

Keywords

Comments

If n is present, then 2*n is also present, and vice versa.
A007283 is included as a subsequence, because it gives the known fixed points of map n -> A163511(n).
Sequence A243071(A364497(.)) sorted into ascending order.

Examples

			16383 is present, because A163511(16383) = 43, as 16383 = 2^14 - 1 and A000040(14) = 43, and 43 is a factor of 16383 = 3*43*127.
536870895 is present, because A163511(536870895) = 1177 (11*107), which divides 536870895 (3*5*11*47*107*647). See also example in A364498.
		

Crossrefs

Positions of 1's in A364492.
Subsequence of A364292.
Cf. A007283 (subsequence), A163511, A364963 (odd terms).

Programs

A292254 a(n) = A292253(A163511(n)).

Original entry on oeis.org

0, 1, 2, 2, 4, 4, 4, 4, 8, 8, 8, 9, 8, 8, 8, 8, 16, 16, 16, 16, 16, 16, 18, 19, 16, 16, 16, 17, 16, 16, 16, 17, 32, 32, 32, 33, 32, 32, 32, 32, 32, 32, 32, 32, 36, 36, 38, 39, 32, 32, 32, 32, 32, 32, 34, 34, 32, 32, 32, 32, 32, 32, 34, 35, 64, 64, 64, 64, 64, 64, 66, 67, 64, 64, 64, 65, 64, 64, 64, 65, 64, 64, 64, 65, 64, 64, 64, 64, 72, 72, 72, 72, 76, 76
Offset: 0

Views

Author

Antti Karttunen, Sep 28 2017

Keywords

Comments

Because A292253(n) = a(A243071(n)), the sequence works as a "masking function" where the 1-bits in a(n) (always a subset of the 1-bits in binary expansion of n) indicate the numbers that are either of the form 12k+1 or of the form 12k+11 in binary tree A163511 (or its mirror image tree A005940) on that trajectory which leads from the root of the tree to the node containing A163511(n).
The AND - XOR formula just restates the fact that J(3|n) = J(-1|n)*J(-3|n), as the Jacobi-symbol is multiplicative (also) with respect to its upper argument.

Crossrefs

Cf also A292247, A292248, A292256, A292264, A292271, A292274, A292592, A292593, A292942, A292944, A292946 (for similarly constructed sequences).

Programs

Formula

a(n) = A292253(A163511(n)).
a(n) = A292264(n) AND (A292274(n) XOR A292942(n)), where AND is bitwise-and (A004198) and XOR is bitwise-XOR (A003987). [See comments.]
For all n >= 0, a(n) + A292944(n) + A292256(n) = n.

A292256 a(n) = A292255(A163511(n)).

Original entry on oeis.org

0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 2, 3, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 4, 4, 6, 6, 0, 0, 0, 0, 0, 0, 2, 3, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 1, 8, 8, 8, 9, 12, 12, 12, 12, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 4, 4, 6, 6, 0, 0, 0, 0, 0, 0, 2, 3, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 2, 2, 0, 0, 0, 0, 0, 0, 2, 2, 16, 16, 16, 16, 16, 16
Offset: 0

Views

Author

Antti Karttunen, Sep 28 2017

Keywords

Comments

Because A292255(n) = a(A243071(n)), the sequence works as a "masking function" where the 1-bits in a(n) (always a subset of the 1-bits in binary expansion of n) indicate the numbers that are either of the form 12k+5 or of the form 12k+7 in binary tree A163511 (or its mirror image tree A005940) on that trajectory which leads from the root of the tree to the node containing A163511(n).
The AND - XOR formulas just restate the fact that J(3|n) = J(-1|n)*J(-3|n), as the Jacobi-symbol is multiplicative (also) with respect to its upper argument.

Crossrefs

Cf. also A292247, A292248, A292254, A292264, A292271, A292274, A292592, A292593, A292942, A292944, A292946 (for similarly constructed sequences).

Programs

Formula

a(n) = A292255(A163511(n)).
a(n) = A292264(n) AND (A292274(n) XOR A292946(n)), where AND is bitwise-and (A004198) and XOR is bitwise-XOR (A003987).
a(n) = A292264(n) AND (A292271(n) XOR A292942(n)). [See comments].
For all n >= 0, a(n) + A292944(n) + A292254(n) = n.

A292942 a(n) = A292941(A163511(n)).

Original entry on oeis.org

0, 1, 2, 2, 4, 4, 4, 4, 8, 8, 8, 9, 8, 8, 8, 9, 16, 16, 16, 16, 16, 16, 18, 19, 16, 16, 16, 16, 16, 16, 18, 18, 32, 32, 32, 33, 32, 32, 32, 33, 32, 32, 32, 32, 36, 36, 38, 39, 32, 32, 32, 33, 32, 32, 32, 32, 32, 32, 32, 33, 36, 36, 36, 37, 64, 64, 64, 64, 64, 64, 66, 67, 64, 64, 64, 64, 64, 64, 66, 66, 64, 64, 64, 65, 64, 64, 64, 65, 72, 72, 72, 72, 76, 76
Offset: 0

Views

Author

Antti Karttunen, Sep 28 2017

Keywords

Comments

Because A292941(n) = a(A243071(n)), the sequence works as a "masking function" where the 1-bits in a(n) (always a subset of the 1-bits in binary expansion of n) indicate which numbers are of the form 6k+1 in binary tree A163511 (or its mirror image tree A005940) on that trajectory which leads from the root of the tree to the node containing A163511(n).
The AND - XOR formula is just a restatement of the fact that J(-3|n) = J(-1|n)*J(3|n), as the Jacobi-symbol is multiplicative (also) with respect to its upper argument.

Crossrefs

Cf. also A292247, A292248, A292254, A292256, A292264, A292271, A292274, A292592, A292593, A292944, A292946 (for similarly constructed sequences).

Programs

Formula

a(n) = A292941(A163511(n)).
a(n) = A292264(n) AND (A292254(n) XOR A292274(n)), where AND is bitwise-and (A004198) and XOR is bitwise-XOR (A003987). [See comments.]
For all n >= 0, a(n) + A292944(n) + A292946(n) = n.

A292946 a(n) = A292945(A163511(n)).

Original entry on oeis.org

0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 2, 2, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 1, 4, 4, 4, 5, 0, 0, 0, 0, 0, 0, 2, 2, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 2, 3, 8, 8, 8, 8, 8, 8, 10, 10, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 1, 4, 4, 4, 5, 0, 0, 0, 0, 0, 0, 2, 2, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 1, 0, 0
Offset: 0

Views

Author

Antti Karttunen, Sep 28 2017

Keywords

Comments

Because A292945(n) = a(A243071(n)), the sequence works as a "masking function" where the 1-bits in a(n) (always a subset of the 1-bits in binary expansion of n) indicate which numbers are of the form 6k+5 in binary tree A163511 (or its mirror image tree A005940) on that trajectory which leads from the root of the tree to the node containing A163511(n).
The AND - XOR formulas just restate the fact that J(-3|n) = J(-1|n)*J(3|n), as the Jacobi-symbol is multiplicative (also) with respect to its upper argument.

Crossrefs

Cf. also A292247, A292248, A292254, A292256, A292264, A292271, A292274, A292592, A292593, A292942, A292944 (for similarly constructed sequences).

Programs

Formula

a(n) = A292945(A163511(n)).
a(n) = A292264(n) AND (A292256(n) XOR A292274(n)), where AND is bitwise-and (A004198) and XOR is bitwise-XOR (A003987).
a(n) = A292264(n) AND (A292254(n) XOR A292271(n)). [See comments.]
For all n >= 0, A292942(n) + A292944(n) + a(n) = n.

A364491 a(n) = n / gcd(n, A163511(n)).

Original entry on oeis.org

0, 1, 1, 1, 1, 5, 1, 7, 1, 1, 5, 11, 1, 13, 7, 15, 1, 17, 1, 19, 5, 7, 11, 23, 1, 5, 13, 27, 7, 29, 15, 31, 1, 11, 17, 7, 1, 37, 19, 39, 5, 41, 7, 43, 11, 15, 23, 47, 1, 49, 5, 51, 13, 53, 27, 5, 7, 19, 29, 59, 15, 61, 31, 63, 1, 65, 11, 67, 17, 23, 7, 71, 1, 73, 37, 15, 19, 11, 39, 79, 5, 3, 41, 83, 7, 17, 43, 87
Offset: 0

Views

Author

Antti Karttunen, Jul 26 2023

Keywords

Comments

Numerator of n / A163511(n).

Crossrefs

Cf. A163511, A364255, A364492 (denominators), A364493, A364494 (positions of 1's).

Programs

  • PARI
    A005940(n) = { my(p=2, t=1); n--; until(!n\=2, if((n%2), (t*=p), p=nextprime(p+1))); t };
    A054429(n) = ((3<<#binary(n\2))-n-1); \\ From A054429
    A163511(n) = if(!n,1,A005940(1+A054429(n)))
    A364491(n) = (n/gcd(n, A163511(n)));
    
  • Python
    from math import gcd
    from sympy import nextprime
    def A364491(n):
        c, p, k = 1, 1, n
        while k:
            c *= (p:=nextprime(p))**(s:=(~k&k-1).bit_length())
            k >>= s+1
        return n//gcd(c*p,n) # Chai Wah Wu, Jul 26 2023

Formula

a(n) = n / A364255(n) = n / gcd(n, A163511(n)).

A366806 Lexicographically earliest infinite sequence such that a(i) = a(j) => A324186(i) = A324186(j) for all i, j >= 0, where A324186 is the sum of odd divisors permuted by A163511.

Original entry on oeis.org

1, 1, 1, 2, 1, 3, 2, 4, 1, 5, 3, 6, 2, 7, 4, 8, 1, 9, 5, 10, 3, 11, 6, 12, 2, 13, 7, 14, 4, 15, 8, 16, 1, 17, 9, 18, 5, 19, 10, 20, 3, 21, 11, 22, 6, 23, 12, 24, 2, 25, 13, 26, 7, 27, 14, 28, 4, 29, 15, 30, 8, 14, 16, 31, 1, 32, 17, 33, 9, 34, 18, 35, 5, 36, 19, 37, 10, 38, 20, 39, 3, 40, 21, 41, 11, 42, 22, 43, 6
Offset: 0

Views

Author

Antti Karttunen, Oct 26 2023

Keywords

Comments

Restricted growth sequence transform of A324186.

Crossrefs

Programs

  • PARI
    up_to = 65537;
    rgs_transform(invec) = { my(om = Map(), outvec = vector(length(invec)), u=1); for(i=1, length(invec), if(mapisdefined(om,invec[i]), my(pp = mapget(om, invec[i])); outvec[i] = outvec[pp] , mapput(om,invec[i],i); outvec[i] = u; u++ )); outvec; };
    A000593(n) = sigma(n>>valuation(n, 2)); \\ From A000593
    A163511(n) = if(!n,1,my(p=2, t=1); while(n>1, if(!(n%2), (t*=p), p=nextprime(1+p)); n >>= 1); (t*p));
    A324186(n) = A000593(A163511(n));
    v366806 = rgs_transform(vector(1+up_to,n,A324186(n-1)));
    A366806(n) = v366806[1+n];

Formula

For all n >= 1, a(n) = a(2*n) = a(A000265(n)).

A324187 a(n) = A106315(A163511(n)).

Original entry on oeis.org

0, 1, 5, 2, 2, 1, 0, 4, 18, 28, 30, 13, 16, 12, 4, 6, 3, 42, 72, 32, 51, 78, 21, 33, 12, 36, 24, 44, 36, 20, 8, 10, 67, 2, 168, 1, 176, 504, 128, 172, 84, 10, 312, 102, 32, 198, 75, 97, 108, 120, 144, 58, 48, 72, 128, 20, 50, 66, 48, 4, 0, 36, 16, 12, 4, 731, 372, 3126, 625, 6, 785, 801, 456, 1332, 768, 1720, 540, 232, 688, 932, 145, 660
Offset: 0

Views

Author

Antti Karttunen, Feb 17 2019

Keywords

Crossrefs

Cf. A324199 (positions of zeros).

Programs

  • PARI
    A106315(n) = (n*numdiv(n) % sigma(n));
    A163511(n) = if(!n,1,my(p=2, t=1); while(n>1, if(!(n%2), (t*=p), p=nextprime(1+p)); n >>= 1); (t*p));
    A324187(n) = A106315(A163511(n));
    
  • PARI
    A324183(n) = if(!n,1,n = ((3<<#binary(n\2))-n-1); my(e=0,m=1); while(n>0, if(!(n%2), m *= (1+e); e=0, e++); n >>= 1); (m*(1+e)));
    A324184(n) = if(!n,1,my(p=2,mp=p*p,m=1); while(n>1, if(n%2, p=nextprime(1+p); mp = p*p, if((2==n)||!(n%4),mp *= p,m *= (mp-1)/(p-1))); n >>= 1); (m*(mp-1)/(p-1)));
    A324187(n) = ((A163511(n)*A324183(n))%A324184(n));

Formula

a(n) = A106315(A163511(n)) = (A163511(n)*A324183(n)) mod A324184(n).
For n > 0, a(n) = A324057(A054429(n)).

A324189 a(n) = A324122(A163511(n)).

Original entry on oeis.org

0, 2, 6, 2, 14, 12, 0, 4, 30, 36, 36, 30, 24, 12, 16, 6, 60, 120, 96, 152, 90, 122, 90, 54, 48, 72, 48, 44, 36, 28, 16, 10, 126, 362, 360, 780, 272, 600, 464, 396, 192, 402, 360, 336, 216, 222, 168, 132, 120, 120, 216, 246, 144, 168, 128, 92, 80, 102, 48, 68, 0, 36, 32, 12, 254, 1092, 1080, 3900, 846, 3122, 2342, 2800, 576, 2016, 1824, 2360, 1080
Offset: 0

Views

Author

Antti Karttunen, Feb 17 2019

Keywords

Crossrefs

Cf. A324199 (positions of zeros).

Programs

  • PARI
    A163511(n) = if(!n,1,my(p=2, t=1); while(n>1, if(!(n%2), (t*=p), p=nextprime(1+p)); n >>= 1); (t*p));
    A324122(n) = (sigma(n) - gcd(sigma(n),n*numdiv(n)));
    A324189(n) = A324122(A163511(n));
    
  • PARI
    A324183(n) = if(!n,1,n = ((3<<#binary(n\2))-n-1); my(e=0,m=1); while(n>0, if(!(n%2), m *= (1+e); e=0, e++); n >>= 1); (m*(1+e)));
    A324184(n) = if(!n,1,my(p=2,mp=p*p,m=1); while(n>1, if(n%2, p=nextprime(1+p); mp = p*p, if((2==n)||!(n%4),mp *= p,m *= (mp-1)/(p-1))); n >>= 1); (m*(mp-1)/(p-1)));
    A324189(n) = (A324184(n) - gcd(A324184(n), A163511(n)*A324183(n)));

Formula

a(n) = A324184(n) - A324188(n) = A324184(n) - gcd(A324184(n),A163511(n)*A324183(n)).
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