A364548 Numbers k such that k divides A005941(k).

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.

Links

Table of n, a(n) for n=1..63.

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

Cf. A005940, A005941, A156552, A364546.

Subsequences: A029747, A364549 (odd terms).

Cf. also A364497.

Sequence in context: A364960 A245709 A364565 * A364544 A253789 A364546

Adjacent sequences: A364545 A364546 A364547 * A364549 A364550 A364551

Keyword

nonn

Author

Antti Karttunen, Jul 28 2023

Status

approved