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