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This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A133659 Primes that are the sum of three consecutive primes as well as the sum of three consecutive composite numbers.

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%I A133659 #7 Sep 16 2015 13:46:08
%S A133659 23,31,41,59,71,109,131,199,211,251,269,311,487,503,701,829,941,1049,
%T A133659 1061,1151,1229,1381,1511,1931,2129,2179,2251,2269,2393,2579,2971,
%U A133659 3041,3271,3329,3581,3851,3889,3911,4289,4451,4481,4679,4987,4999
%N A133659 Primes that are the sum of three consecutive primes as well as the sum of three consecutive composite numbers.
%H A133659 R. J. Mathar, <a href="/A133659/b133659.txt">Table of n, a(n) for n=1..287</a>
%F A133659 Equals A034962 INTERSECT A060328. - _R. J. Mathar_, Jan 11 2008
%e A133659 a(3) = 41 because 41 = 11+13+17 and 41 = 12+14+15.
%t A133659 a = {}; For[n = 2, n < 10000, n++, If[ ! PrimeQ[n], AppendTo[a, n + Select[Range[n + 1, n + 10], ! PrimeQ[ # ] &][[1]] + Select[Range[n + 1, n + 10], ! PrimeQ[ # ] &][[2]]]]]; b = Table[Prime[i] + Prime[i + 1] + Prime[i + 2], {i, 1, 10000}]; Select[Intersection[a, b], PrimeQ[ # ] &] (* _Stefan Steinerberger_, Dec 30 2007 *)
%Y A133659 Cf. A034962, A060328.
%K A133659 easy,nonn
%O A133659 1,1
%A A133659 _Randy L. Ekl_, Dec 28 2007
%E A133659 More terms from _Stefan Steinerberger_, Dec 30 2007