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Terms in A061725 that are of form 3*prime.
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%I #6 Oct 13 2013 17:43:14

%S 6,51,123,291,843,1371,1851,2811,5331,6243,6891,9411,18771,36483,

%T 54291,63003,69171,72363,73443,76731,78963,128883,143643,151323,

%U 187491,212523,229443,271443,292683,332931,361203,398163,418611,458331,477483,516963

%N Terms in A061725 that are of form 3*prime.

%C 3|p^2+2 for all p except 3 hence 3|A061725(n) for all n except n=2. If p^2+2 is semiprime it is of form 3*prime.

%o (PARI) lista(nn) = {vec = vector(nn, i, prime(i)^2 + 2); pp = select(i->((bigomega(i) == 2) && !(i % 3)), vec); print(pp);} \\ _Michel Marcus_, Oct 13 2013

%Y Cf. A061725 (p^2+2 where p=prime).

%K nonn

%O 1,1

%A _Zak Seidov_, Dec 22 2007

%E Typo in Comment corrected by Shai Covo (green355(AT)netvision.net.il), Oct 11 2010