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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A334093 Primes p for which A329697(p) == 3.

Original entry on oeis.org

19, 23, 29, 31, 37, 53, 61, 73, 83, 89, 101, 103, 113, 241, 353, 389, 401, 409, 449, 577, 773, 1097, 1153, 1283, 1361, 1409, 1543, 1553, 1601, 3089, 3329, 5441, 6529, 7681, 13313, 15361, 17477, 18433, 25601, 26113, 49157, 49409, 61441, 82241, 83969, 87041, 98689, 114689, 147457, 295937, 327689, 328961, 417793
Offset: 1

Views

Author

Antti Karttunen, Apr 14 2020

Keywords

Comments

Primes p of the form of the form A334102(n) + 1, for some n >= 1.

Crossrefs

Cf. A329697, A334102, primes in A334103.

Programs

A334094 Primes p for which A329697(p) == 4.

Original entry on oeis.org

43, 47, 59, 67, 71, 79, 107, 109, 131, 149, 151, 157, 167, 179, 181, 227, 233, 239, 251, 281, 293, 307, 313, 337, 433, 443, 521, 593, 601, 613, 673, 809, 821, 823, 881, 929, 953, 971, 977, 1021, 1201, 1217, 1249, 1637, 1697, 1931, 2081, 2113, 2309, 2657, 2689, 2741, 2789, 2819, 3203, 3209, 3299, 3457, 3469, 3593, 3617, 3847, 3881, 4001
Offset: 1

Views

Author

Antti Karttunen, Apr 14 2020

Keywords

Comments

Primes p of the form of the form A334103(n) + 1, for some n >= 1.

Crossrefs

Programs

A334106 Numbers n for which A329697(n) == 6.

Original entry on oeis.org

283, 301, 329, 343, 347, 361, 379, 381, 383, 387, 399, 413, 417, 419, 423, 431, 437, 441, 463, 469, 473, 483, 487, 489, 491, 497, 509, 513, 517, 519, 523, 529, 531, 539, 547, 551, 553, 557, 559, 566, 567, 571, 573, 589, 591, 597, 599, 602, 603, 609, 611, 621, 627, 631, 633, 635, 637, 639, 643, 645, 649, 651, 653, 658, 665
Offset: 1

Views

Author

Antti Karttunen, Apr 14 2020

Keywords

Crossrefs

Row 6 of A334100.
Cf. A334096 (primes present).

Programs

A334095 Primes p for which A329697(p) == 5.

Original entry on oeis.org

127, 139, 163, 173, 191, 197, 199, 211, 223, 229, 263, 269, 271, 277, 311, 317, 331, 349, 359, 367, 373, 397, 421, 439, 457, 461, 467, 479, 499, 503, 541, 563, 569, 587, 607, 617, 619, 647, 661, 677, 701, 733, 739, 751, 761, 857, 877, 887, 919, 937, 997, 1009, 1031, 1049, 1061, 1069, 1123, 1187, 1193, 1213, 1229, 1231
Offset: 1

Views

Author

Antti Karttunen, Apr 14 2020

Keywords

Comments

Primes p of the form of the form A334104(n) + 1, for some n >= 1.

Crossrefs

Programs

A334096 Primes p for which A329697(p) == 6.

Original entry on oeis.org

283, 347, 379, 383, 419, 431, 463, 487, 491, 509, 523, 547, 557, 571, 599, 631, 643, 653, 683, 691, 709, 719, 727, 743, 757, 787, 797, 811, 829, 853, 859, 907, 911, 941, 991, 1013, 1033, 1051, 1087, 1091, 1093, 1109, 1117, 1129, 1151, 1163, 1171, 1181, 1277, 1289, 1381, 1399, 1451, 1453, 1493, 1511, 1523, 1559, 1571, 1583, 1607
Offset: 1

Views

Author

Antti Karttunen, Apr 14 2020

Keywords

Comments

Primes p of the form of the form A334105(n) + 1, for some n >= 1.

Crossrefs

Programs

A334105 Numbers m for which A329697(m) = 5.

Original entry on oeis.org

127, 129, 133, 139, 141, 147, 161, 163, 171, 173, 177, 189, 191, 197, 199, 201, 203, 207, 209, 211, 213, 215, 217, 223, 229, 231, 235, 237, 243, 245, 247, 253, 254, 258, 259, 261, 263, 266, 269, 271, 273, 277, 278, 279, 282, 285, 294, 295, 297, 299, 311, 315, 317, 319, 321, 322, 326, 327, 331, 333, 335, 341, 342, 345, 346, 349, 351
Offset: 1

Views

Author

Antti Karttunen, Apr 14 2020

Keywords

Examples

			127 = 63*2 + 1 is a term, as 127 is a prime and 63 is in A334104 as A329697(63) = 4.
2^32 -1 = 4294967295 = 3*5*17*257*65537 is a term as it is a product of five Fermat primes, thus in five steps all odd primes can be eliminated with p -> (p-1) map.
Likewise for 1442840405 = 5 * 17 * 257^3. (The first term with binary weight = 24).
		

Crossrefs

Row 5 of A334100.
Cf. A334095 (primes present).

Programs

  • Mathematica
    Position[Array[Length@ NestWhileList[# - #/FactorInteger[#][[-1, 1]] &, #, # != 2^IntegerExponent[#, 2] &] - 1 &, 360], 5][[All, 1]] (* Michael De Vlieger, Apr 30 2020 *)
  • PARI
    A329697(n) = if(!bitand(n,n-1),0,1+A329697(n-(n/vecmax(factor(n)[, 1]))));
    isA334105(n) = (5==A329697(n));

A334107 a(n) = A329697(A122111(n)).

Original entry on oeis.org

0, 0, 0, 1, 0, 1, 0, 1, 2, 1, 0, 1, 0, 1, 2, 2, 0, 2, 0, 1, 2, 1, 0, 2, 3, 1, 2, 1, 0, 2, 0, 2, 2, 1, 3, 3, 0, 1, 2, 2, 0, 2, 0, 1, 2, 1, 0, 2, 4, 3, 2, 1, 0, 3, 3, 2, 2, 1, 0, 3, 0, 1, 2, 2, 3, 2, 0, 1, 2, 3, 0, 3, 0, 1, 3, 1, 4, 2, 0, 2, 4, 1, 0, 3, 3, 1, 2, 2, 0, 3, 4, 1, 2, 1, 3, 2, 0, 4, 2, 4, 0, 2, 0, 2, 3
Offset: 1

Views

Author

Antti Karttunen, Apr 29 2020

Keywords

Crossrefs

Programs

  • Mathematica
    Map[Length@ NestWhileList[# - #/FactorInteger[#][[-1, 1]] &, #, # != 2^IntegerExponent[#, 2] &] - 1 &, Array[Times @@ Table[Prime[LengthWhile[#1, # >= j &] /. 0 -> 1], {j, #2}] & @@ {#, Max[#]} &@ PrimePi@ Flatten[ConstantArray[#1, {#2}] & @@@ FactorInteger@ #] &, 105] ] (* Michael De Vlieger, May 14 2020, after Robert G. Wilson v at A329697 *)
  • PARI
    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)};
    A122111(n) = if(1==n,n,prime(bigomega(n))*A122111(A064989(n)));
    A329697(n) = if(!bitand(n,n-1),0,1+A329697(n-(n/vecmax(factor(n)[, 1]))));
    A334107(n) = A329697(A122111(n));

Formula

a(n) = A329697(A122111(n)) = A329697(A322865(n)).
a(n) = A329697(A105560(n)) + a(A064989(n)).
For n >= 1, a(A001248(n)) = n, and these seem to be also the first occurrences of each n.

A334861 a(n) = A329697(n) + A331410(n).

Original entry on oeis.org

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

Views

Author

Antti Karttunen, May 14 2020

Keywords

Comments

Completely additive because A329697 and A331410 are. No 1's occur as terms.

Crossrefs

Cf. A000079 (positions of zeros), A329697, A331410, A334862.

Programs

  • PARI
    A329697(n) = { my(f=factor(n)); sum(k=1,#f~,if(2==f[k,1],0,f[k,2]*(1+A329697(f[k,1]-1)))); };
    A331410(n) = { my(f=factor(n)); sum(k=1,#f~,if(2==f[k,1],0,f[k,2]*(1+A331410(f[k,1]+1)))); };
    A334861(n) = (A329697(n)+A331410(n));
    \\ Or alternatively as:
    A334861(n) = { my(f=factor(n)); sum(k=1,#f~,if(2==f[k,1],0,f[k,2]*(2+A329697(f[k,1]-1)+A331410(f[k,1]+1)))); };

Formula

a(n) = A329697(n) + A331410(n).
a(2) = 0, a(p) = 2+A329697(p-1)+A331410(p+1) for odd primes p, a(m*n) = a(m)+a(n), if m,n > 1.

A335875 a(n) = min(A329697(n), A331410(n)).

Original entry on oeis.org

0, 0, 1, 0, 1, 1, 1, 0, 2, 1, 2, 1, 2, 1, 2, 0, 1, 2, 3, 1, 2, 2, 2, 1, 2, 2, 3, 1, 3, 2, 1, 0, 3, 1, 3, 2, 3, 3, 3, 1, 2, 2, 3, 2, 3, 2, 2, 1, 2, 2, 2, 2, 3, 3, 3, 1, 4, 3, 4, 2, 2, 1, 3, 0, 3, 3, 4, 1, 3, 3, 3, 2, 3, 3, 3, 3, 3, 3, 3, 1, 4, 2, 3, 2, 2, 3, 4, 2, 3, 3, 3, 2, 2, 2, 4, 1, 2, 2, 4, 2, 3, 2, 3, 2, 4
Offset: 1

Views

Author

Antti Karttunen, Jun 29 2020

Keywords

Examples

			A329697(67) = A331410(67) = 4, thus a(67) = min(4,4) = 4.
A329697(15749) = 9 and A331410(15749) = 10, thus a(15749) = 9.
		

Crossrefs

Programs

Formula

a(n) = min(A329697(n), A331410(n)).
For all n >= 1, A335904(n) >= A335884(n) >= A335881(n) >= a(n) >= A335885(n).

A336471 Lexicographically earliest infinite sequence such that a(i) = a(j) => A329697(i) = A329697(j) and A336158(i) = A336158(j), for all i, j >= 1.

Original entry on oeis.org

1, 1, 2, 1, 2, 2, 3, 1, 4, 2, 3, 2, 3, 3, 5, 1, 2, 4, 6, 2, 7, 3, 6, 2, 4, 3, 8, 3, 6, 5, 6, 1, 7, 2, 7, 4, 6, 6, 7, 2, 3, 7, 9, 3, 10, 6, 9, 2, 11, 4, 5, 3, 6, 8, 7, 3, 12, 6, 9, 5, 6, 6, 13, 1, 7, 7, 9, 2, 12, 7, 9, 4, 6, 6, 10, 6, 12, 7, 9, 2, 14, 3, 6, 7, 5, 9, 12, 3, 6, 10, 12, 6, 12, 9, 12, 2, 3, 11, 13, 4, 6, 5, 6, 3, 15
Offset: 1

Views

Author

Antti Karttunen, Jul 22 2020

Keywords

Comments

Restricted growth sequence transform of the ordered pair [A329697(n), A336158(n)].
For all i, j:
A336470(i) = A336470(j) => a(i) = a(j)
a(i) = a(j) => A336396(i) = A336396(j),
a(i) = a(j) => A336469(i) = A336469(j) => A336477(i) = A336477(j).
This sequence has an ability to see where the terms of A003401 are, as they are the indices of zeros in A336469. Specifically, they are numbers k that satisfy the condition A329697(k) = A001221(A336158(k)), i.e., numbers for which A329697(k) is equal to the number of distinct prime divisors of the odd part of k. See also comments in array A334100.

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; };
    A000265(n) = (n>>valuation(n,2));
    A046523(n) = { my(f=vecsort(factor(n)[, 2], , 4), p); prod(i=1, #f, (p=nextprime(p+1))^f[i]); };  \\ From A046523
    A336158(n) = A046523(A000265(n));
    A329697(n) = if(!bitand(n,n-1),0,1+A329697(n-(n/vecmax(factor(n)[, 1]))));
    Aux336471(n) = [A329697(n), A336158(n)];
    v336471 = rgs_transform(vector(up_to, n, Aux336471(n)));
    A336471(n) = v336471[n];
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