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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.

A112681 Primes such that the sum of the predecessor and successor primes is divisible by 3.

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%I A112681 #12 Aug 18 2020 12:37:47
%S A112681 23,29,31,37,47,59,61,67,73,79,83,89,131,137,151,163,167,179,199,223,
%T A112681 233,239,251,269,271,277,331,337,353,359,367,379,383,389,433,439,443,
%U A112681 449,467,479,503,521,523,547,557,569,571,577,587,599,601,613,619,631
%N A112681 Primes such that the sum of the predecessor and successor primes is divisible by 3.
%H A112681 Harvey P. Dale, <a href="/A112681/b112681.txt">Table of n, a(n) for n = 1..1000</a>
%e A112681 23 is in the sequence because 19+29=48 and 3|48.
%e A112681 29 is in the sequence because 29+31=60 and 3|60.
%t A112681 Prime@Select[Range[2, 117], Mod[Prime[ # - 1] + Prime[ # + 1], 3] == 0 &] (* _Robert G. Wilson v_, Jan 11 2006 *)
%t A112681 Select[Partition[Prime[Range[150]],3,1],Divisible[#[[1]]+#[[3]],3]&][[All,2]] (* _Harvey P. Dale_, Aug 18 2020 *)
%Y A112681 Analogs where 3 is replaced by other primes:
%Y A112681 Divisor: ..3 .......5 .......7 ......11 ......13 ......17 ......19 ......23 ......29 ......31 ......37 ......41 ......43
%Y A112681 Cf. A112681, A112794, A112731, A112789, A112795, A112796, A112804, A112847, A112859, A113155, A113156, A113157, A113158.
%K A112681 easy,nonn
%O A112681 1,1
%A A112681 _Carlos Alves_, Dec 30 2005