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%I #29 Nov 22 2023 22:07:11
%S 2,3,7,13,7,31,43,19,73,13,37,19,157,61,211,241,13,307,7,127,421,463,
%T 13,79,601,31,37,757,271,67,19,331,151,1123,397,97,43,67,1483,223,547,
%U 1723,139,631,283,109,103,61,181,43,2551,379,919,409,2971,79,103,3307,163
%N Greatest prime factor of n^3 + 1.
%C Record values appear to match the terms of A002383 for n>1. - _Bill McEachen_, Oct 18 2023
%H R. J. Mathar and T. D. Noe, <a href="/A081256/b081256.txt">Table of n, a(n) for n = 1..10000</a> (first 5000 terms from R. J. Mathar)
%F a(n) = A006530(A001093(n)). - _M. F. Hasler_, Jun 13 2018
%p A081256 := proc(n)
%p A006530(n^3+1) ;
%p end proc:
%p seq(A081256(n),n=1..20) ; # _R. J. Mathar_, Feb 13 2014
%t Table[Max[Transpose[FactorInteger[n^3 + 1]][[1]]], {n, 25}]
%o (PARI) a(n)=my(f=factor(n^3+1)); f[#f~,1] \\ _Charles R Greathouse IV_, Mar 08 2017
%o (PARI) A081256(n)=vecmax(factor(n^3+1)[,1]) \\ It seems slightly slower to get the last element using ...[-1..-1][1]. - _M. F. Hasler_, Jun 15 2018
%Y Cf. A081257, A081258, A096173, A096174.
%Y Cf. A006530, A001093, A002383.
%K easy,nonn
%O 1,1
%A _Jan Fricke_, Mar 14 2003
%E More terms from _Harvey P. Dale_, Mar 22 2003
%E More terms from _Hugo Pfoertner_, Jun 20 2004
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