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%I #7 Mar 04 2018 10:35:43
%S -3,0,0,4,0,5,0,12,6,7,0,15,0,9,8,28,0,20,0,21,10,13,0,35,10,15,24,27,
%T 0,0,0,60,14,19,12,54,0,21,16,49,0,0,0,39,32,25,0,75,14,42,20,45,0,65,
%U 16,63,22,31,0,0,0,33,40,124,18,0,0,57,26,0,0,122
%N a(n) = (sigma(n)-n-1)*(3-omega(n)).
%C If n is prime, then a(n) = 0. If n is semiprime, then a(n) = sopfr(n).
%H Antti Karttunen, <a href="/A288654/b288654.txt">Table of n, a(n) for n = 1..65537</a>
%t Table[(DivisorSigma[1, n] - n - 1) (3 - PrimeNu[n]), {n, 100}]
%o (PARI) A288654(n) = ((sigma(n)-n-1)*(3-omega(n))); \\ _Antti Karttunen_, Mar 04 2018
%Y Cf. A000203 (sigma), A001221 (omega), A001414 (sopfr), A048050 (Chowla's function).
%K sign,easy
%O 1,1
%A _Wesley Ivan Hurt_, Jun 12 2017
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