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A071217 Numbers k such that the largest prime factor of the sum of successive primes p(k) + p(k+1) is greater than k. 1

%I

%S 1,9,11,12,19,23,24,29,31,32,51,54,58,63,67,71,75,76,77,84,86,87,93,

%T 95,97,103,108,110,124,128,136,151,158,159,164,169,188,191,192,200,

%U 202,205,208,210,211,216,227,232,241,243,245,246,247,252,265,273,278,282

%N Numbers k such that the largest prime factor of the sum of successive primes p(k) + p(k+1) is greater than k.

%F A071216(k) > k.

%e p(9) + p(10) = 23 + 29 = 52 = 2*2*13 and 13 > 10, so index 9 is here; it is the 2nd term.

%t pf[x_] := Part[Reverse[Flatten[FactorInteger[x]]], 2] Do[s=pf[Prime[n+1]+Prime[n]]; If[Greater[s, n], Print[n]], {n, 1, 1000}]

%Y Cf. A001043, A006530, A071216.

%K nonn

%O 1,2

%A _Labos Elemer_, May 17 2002

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Last modified May 28 16:37 EDT 2022. Contains 354119 sequences. (Running on oeis4.)