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A112789 Primes such that the sum of the predecessor and successor primes is divisible by 11.

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%I A112789 #9 Nov 21 2013 12:48:45
%S A112789 31,43,67,109,131,139,191,617,727,881,911,937,953,991,1049,1289,1381,
%T A112789 1429,1543,1571,1619,1657,1693,1721,1723,1777,1783,1871,1979,2251,
%U A112789 2311,2341,2377,2441,2531,2579,2837,2953,3061,3221,3257,3557,3559,3631,3673
%N A112789 Primes such that the sum of the predecessor and successor primes is divisible by 11.
%F A112789 a(n) = prime(i) is in this sequence iff prime(i-1)+prime(i+1) = 0 mod 11. a(n) = A000040(i) is in this sequence iff A000040(i-1)+A000040(i+1) = 0 mod 11.
%e A112789 a(1) = 31 because prevprime(31) + nextprime(31) = 29 + 37 = 66 = 11 * 6.
%e A112789 a(2) = 43 because prevprime(43) + nextprime(43) = 41 + 47 = 88 = 11 * 8.
%e A112789 a(3) = 67 because prevprime(67) + nextprime(67) = 61 + 71 = 132 = 11 * 12.
%e A112789 a(4) = 109 because prevprime(109) + nextprime(109) = 107 + 113 = 220 = 11 * 20.
%t A112789 Prime@ Select[Range[2, 515], Mod[Prime[ # - 1] + Prime[ # + 1], 11] == 0 &] (* _Robert G. Wilson v_ *)
%t A112789 Transpose[Select[Partition[Prime[Range[550]],3,1],Divisible[First[#]+ Last[#], 11]&]][[2]] (* _Harvey P. Dale_, Jul 22 2011 *)
%Y A112789 Cf. A000040, A112681, A112794, A112731, A112789, A112795, A112796, A112804, A112847, A112859, A113155, A113156, A113157, A113158.
%K A112789 easy,nonn
%O A112789 1,1
%A A112789 _Jonathan Vos Post_, Jan 01 2006
%E A112789 More terms from _Robert G. Wilson v_, Jan 05 2006