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A364548
Numbers k such that k divides A005941(k).
5
1, 2, 3, 4, 5, 6, 8, 10, 12, 16, 20, 24, 32, 40, 48, 64, 80, 96, 97, 128, 160, 192, 194, 256, 320, 345, 384, 388, 512, 549, 640, 690, 768, 776, 1024, 1093, 1098, 1280, 1380, 1536, 1552, 2048, 2186, 2196, 2560, 2760, 3072, 3104, 4096, 4372, 4392, 5120, 5520, 6144, 6208, 8192, 8744, 8784, 10240, 11040, 12288, 12416, 16384
OFFSET
1,2
COMMENTS
Numbers k such that k divides 1+A156552(k).
Sequence A005940(A364546(.)) sorted into ascending order.
If k is a term, then also 2*k is present in this sequence, and vice versa.
PROG
(PARI)
A005941(n) = { my(f=factor(n), p, 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]); (1+res) }; \\ (After David A. Corneth's program for A156552)
isA364548(n) = !(A005941(n)%n);
CROSSREFS
Subsequences: A029747, A364549 (odd terms).
Cf. also A364497.
Sequence in context: A364960 A245709 A364565 * A364544 A253789 A364546
KEYWORD
nonn
AUTHOR
Antti Karttunen, Jul 28 2023
STATUS
approved