%I A122488
%S A122488 1,3,4,5,6,8,9,10,11,15,20,21,22,29,30,33,35,36,40,42,45,47,48,50,54,57,
%T A122488 59,60,64,66,69,72,75,76,77,78,80,81,82,84,86,89,95,96,100,102,108,110,
%U A122488 111,112,113,116,123,125,130,131,132,134,136,143,146,147,148,152,153
%N A122488 Numbers n such that 1+2n+3n^2 is semiprime.
%C A122488 Cf. A086285 (Numbers n such that 1+2n+3n^2 is prime).
%e A122488 n=3 is OK because 1+2n+3n^2=34=2*17 (semiprime)
%e A122488 n=4 is OK because 1+2n+3n^2=57=3*19 (semiprime), etc.
%Y A122488 Cf. A086285.
%Y A122488 Sequence in context: A099352 A047207 A039132 this_sequence A039095 A001957
A100966
%Y A122488 Adjacent sequences: A122485 A122486 A122487 this_sequence A122489 A122490
A122491
%K A122488 nonn
%O A122488 1,2
%A A122488 Zak Seidov (zakseidov(AT)yahoo.com), Oct 20 2006
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