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%I #13 Apr 28 2016 22:51:34
%S 12,45,175,539,1573,2873,5491,8303,15341,26071,35557,56129,72283,
%T 86903,117077,165731,212341,249307,318719,367993,420991,518003,613121,
%U 768337,950309,1050703,1135163,1247941,1342553,1621663,2112899,2351057,2608891,2878829,3352351
%N a(n) = (p_n)^2 * p_{n+1}, where p_n is the n-th prime, A000040(n).
%C Subsequence of A014612: a(1)=12=A014612(2), a(2)=45=A014612(10) - _Zak Seidov_, Apr 26 2016
%H Harvey P. Dale, <a href="/A251720/b251720.txt">Table of n, a(n) for n = 1..1000</a>
%F a(n) = A000040(n) * A000040(n) * A000040(n+1).
%F a(n) = A000040(n) * A006094(n).
%F a(n) = A001248(n) * A000040(n+1).
%t a251720[n_Integer] := Prime[#]^2*Prime[# + 1] & /@ Range[n]; a251720[35] (* _Michael De Vlieger_, Dec 14 2014 *)
%t #[[1]]^2 #[[2]]&/@Partition[Prime[Range[40]],2,1] (* _Harvey P. Dale_, Mar 12 2015 *)
%o (Scheme, three versions)
%o (define (A251720 n) (* (A000040 n) (A000040 n) (A000040 (+ 1 n))))
%o (define (A251720 n) (* (A000040 n) (A006094 n)))
%o (define (A251720 n) (* (A001248 n) (A000040 (+ n 1))))
%Y Cf. A000040, A001248, A006094, A250477, A014612, A268733.
%K nonn
%O 1,1
%A _Antti Karttunen_, Dec 14 2014
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