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Indices of zeros in A085102.
1

%I #9 Aug 23 2014 15:18:02

%S 1,8,12,18,22,27,32,36,39,42,45,48,49,50,54,62,66,68,69,70,75,77,81,

%T 82,87,91,94,95,98,99,100,102,104,106,110,115,116,119,121,122,125,128,

%U 129,132,133,134,138,142,146,150,154,159,160,162,165,169,170,171,175,176

%N Indices of zeros in A085102.

%e 8 is a member as 8, 8+4, 8+4+2 or 8+4+2+1 (8,12,14 and 15) all are composite.

%o (PARI) isok(n) = {d = divisors(n); p = 0; forstep (i=#d, 1, -1, p += d[i]; if (isprime(p), return (0));); return (1);} \\ _Michel Marcus_, Sep 17 2013

%Y Cf. A085102.

%K nonn

%O 1,2

%A _Amarnath Murthy_ and Meenakshi Srikanth (menakan_s(AT)yahoo.com), Jul 03 2003

%E More terms from _David Wasserman_, Jan 26 2005