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Numbers k for which A156552(k) > k.
3

%I #7 Jul 29 2023 14:36:56

%S 7,11,13,14,17,19,22,23,26,28,29,31,33,34,37,38,39,41,43,44,46,47,51,

%T 52,53,56,57,58,59,61,62,65,66,67,68,69,71,73,74,76,78,79,82,83,85,86,

%U 87,88,89,92,93,94,95,97,101,102,103,104,106,107,109,111,112,113,114,115,116,117,118,119,122,123,124,127

%N Numbers k for which A156552(k) > k.

%C Numbers k such that A005941(k) > k.

%C If k is a term, then also 2*k is present in this sequence, and vice versa.

%o (PARI)

%o A156552(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]); res };

%o isA364562(n) = (A156552(n) > n);

%Y Positions of strictly positive terms in A364559.

%Y Cf. A005941, A156552, A364560 (complement).

%K nonn

%O 1,1

%A _Antti Karttunen_, Jul 28 2023