A162731 - OEIS

%I #10 Aug 29 2021 18:57:06

%S 6,10,15,18,24,26,27,39,42,42,45,50,60,63,66,65,70,74,75,90,91,96,99,

%T 100,105,111,114,114,122,120,125,135,140,146,150,147,162,160,165,168,

%U 170,171,170,175,183,186,185,190,204,210,219,225,224,234,231,231,242,238,243,250

%N a(n) is the n-th triprime (A014612) minus its central prime factor.

%F a(n) = A014612(n) - A162361(n).

%e a(1) =  6 = 2*2*2 - 2;

%e a(2) = 10 = 2*2*3 - 2;

%e a(3) = 15 = 2*3*3 - 3;

%e a(4) = 18 = 2*2*5 - 2;

%e a(5) = 24 = 3*3*3 - 3.

%Y Cf. A014612, A162361.

%K nonn,less

%O 1,1

%A _Juri-Stepan Gerasimov_, Jul 12 2009

%E Definition reformulated, a(11), a(38) etc. corrected by _R. J. Mathar_, Jul 16 2009