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, 9, 11, 12, 19, 23, 24, 29, 31, 32, 51, 54, 58, 63, 67, 71, 75, 76, 77, 84, 86, 87, 93, 95, 97, 103, 108, 110, 124, 128, 136, 151, 158, 159, 164, 169, 188, 191, 192, 200, 202, 205, 208, 210, 211, 216, 227, 232, 241, 243, 245, 246, 247, 252, 265, 273, 278, 282

Offset: 1

Author

Labos Elemer, May 17 2002

Keywords

• nonn

Examples

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

Crossrefs

Cf. A001043, A006530, A071216.

Programs

Mathematica

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}]

Formula

A071216(k) > k.