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%I #10 Jan 16 2019 04:14:47
%S 14,20,24,26,27,38,44,46,62,68,74,86,92,94,105,106,112,116,122,124,
%T 125,126,134,146,150,152,158,160,164,166,171,178,180,188,192,194,195,
%U 206,208,212,216,218,226,231,232,234,236,243,244,254,255,261,262,272,275
%N Composites whose sum of prime factors is an odd nonprime (counted with multiplicity).
%e 14 is a term because 14 = 2*7 and 2+7 = 9 (an odd nonprime);
%e 20 is a term because 20 = 2*2*5 and 2+2+5 = 9,
%e 24 is a term because 24 = 2*2*2*3 and 2+2+2+3 = 9;
%e 26 is a term because 26 = 2*13 and 2+13 = 15 (also an odd nonprime).
%p ifac := proc (n) local L, x: L := ifactors(n)[2]: map(proc (x) options operator, arrow: seq(x[1], j = 1 .. x[2]) end proc, L) end proc: a := proc (n) local b: b := add(ifac(n)[j], j = 1 .. nops(ifac(n))): if isprime(n) = false and `mod`(b, 2) = 1 and isprime(b) = false then n else end if end proc: seq(a(n), n = 1 .. 280); # _Emeric Deutsch_, Jan 27 2009
%Y Cf. A002808, A036349, A046363, A141468.
%K nonn
%O 1,1
%A _Juri-Stepan Gerasimov_, Jan 04 2009
%E Corrected (removed 81; added 126, 158) and extended by _Emeric Deutsch_, Jan 27 2009
%E Example section edited by _Jon E. Schoenfield_, Jan 15 2019
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