A166686 - OEIS

%I #9 Apr 24 2014 09:59:52

%S 1,2,8,9,13,14,16,17,30,31,33,34,53,59,61,65,80,85,89,92,94,96,97,103,

%T 113,116,117,121,127,128,142,143,160,163,180,182,188,189,206,208,216,

%U 221,227,235,236,242,255,256,261,262,265,271,294,297,298,300,304,315

%N Numbers m such that m plus the sum of the indices of the prime factors of the m-th composite (counted with multiplicity) is prime.

%e 1st composite = 4 = 2*2 = (1st prime)*(1st prime) and 1+1+1=3 (prime), so 1 is in the sequence.

%e 2nd composite = 6 = 2*3 = (1st prime)*(2nd prime) and 2+1+2=5 (prime), so 2 is in the sequence.

%Y Cf. A000040, A002808.

%K nonn

%O 1,2

%A _Juri-Stepan Gerasimov_, Oct 18 2009

%E 6 removed, 49 removed, 94 inserted, 102 removed, 103 inserted by _R. J. Mathar_, Oct 28 2009

%E Definition reworded by _Jon E. Schoenfield_, Apr 15 2014