A122037 - OEIS

A122037

Largest prime factor of number equal to the arithmetic mean of four successive primes.

3, 3, 5, 3, 11, 5, 19, 7, 23, 11, 5, 17, 3, 29, 17, 7, 3, 19, 5, 127, 139, 3, 149, 31, 11, 7, 181, 31, 13, 5, 43, 19, 29, 241, 19, 23, 13, 53, 5, 139, 97, 17, 13, 53, 37, 31, 11, 17, 11, 127, 43, 19, 7, 71, 431, 7, 149, 11, 79, 37, 163, 11, 127, 257, 41, 271, 23, 43, 113, 19, 3

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OFFSET

1,1

LINKS

Harvey P. Dale, Table of n, a(n) for n = 1..1000

FORMULA

a(n) = A006530(A102655(n)).

MATHEMATICA

FactorInteger[ # ][[ -1, 1]] & /@ Select[Table[Sum[Prime[k], {k, n, n + 3}]/4, {n, 120}], IntegerQ] (* Ray Chandler, Sep 25 2006 *)

FactorInteger[#][[-1, 1]]&/@Select[Mean/@Partition[Prime[Range[ 200]], 4, 1], IntegerQ] (* Harvey P. Dale, May 21 2014 *)

CROSSREFS

Cf. A006530, A102655.