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Numbers m such that A112276(m) is composite.
2

%I #13 Sep 07 2024 08:55:13

%S 8,14,20,21,24,26,32,33,34,38,44,45,48,50,54,55,56,57,62,63,64,68,74,

%T 75,76,80,81,84,85,86,90,91,92,93,94,98,104,105,110,114,115,116,117,

%U 118,119,120,122,123,124,128,132,133,135,140,141,142,143,144,145,147,152

%N Numbers m such that A112276(m) is composite.

%H Amiram Eldar, <a href="/A112277/b112277.txt">Table of n, a(n) for n = 1..10000</a>

%F A000005(a(n)) <= A000005(A112276(a(n))).

%F A066247(A112276(a(n))) = 1.

%t f[1] = 1; f[n_] := Module[{m = n + 1, d = DivisorSigma[0, n]}, While[DivisorSigma[0, m] > d, m++]; m]; Select[Range[150], CompositeQ[f[#]] &] (* _Amiram Eldar_, Feb 03 2020 *)

%Y Cf. A000005, A066247, A112276.

%K nonn

%O 1,1

%A _Reinhard Zumkeller_, Sep 01 2005