A329604 Numbers k such that A156552(k) == 1 (mod 3); numbers k for which A156552(2*k) is a multiple of 3.

2, 5, 8, 11, 15, 17, 18, 20, 23, 31, 32, 33, 41, 42, 44, 45, 47, 50, 51, 59, 60, 67, 68, 69, 72, 73, 77, 78, 80, 83, 92, 93, 97, 98, 99, 103, 109, 110, 114, 119, 123, 124, 125, 127, 128, 132, 135, 137, 141, 149, 153, 157, 161, 162, 164, 167, 168, 170, 174, 176, 177, 179, 180, 182, 188, 191, 197, 200, 201, 204, 207, 210, 211, 217, 219, 221, 222

Offset

1,1

Comments

Even terms of A329609, divided by two.

Numbers k for which A156552(k) == 1 (mod 3). - Antti Karttunen, Feb 27 2020

Links

Antti Karttunen, Table of n, a(n) for n = 1..20000

Prog

(PARI)
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
isA329604(n) = !(A156552(2*n)%3);

Crossrefs

Sequence A329603 sorted into ascending order.

Positions of 1's in A329903 and in A332814.

Cf. A156552, A329609.

Cf. A001105 (subsequence apart from the initial 0).

Cf. A031368 (a subsequence of prime terms).

Cf. also A332812, A324814, A332821.

Sequence in context: A356447 A353985 A118518 * A190079 A184872 A163249

Adjacent sequences: A329601 A329602 A329603 * A329605 A329606 A329607

Keyword

nonn

Author

Antti Karttunen, Nov 21 2019

Extensions

New primary definition added by Antti Karttunen, Mar 01 2020

Status

approved