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A329604
Numbers k such that A156552(k) == 1 (mod 3); numbers k for which A156552(2*k) is a multiple of 3.
11
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
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. 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
KEYWORD
nonn
AUTHOR
Antti Karttunen, Nov 21 2019
EXTENSIONS
New primary definition added by Antti Karttunen, Mar 01 2020
STATUS
approved