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URL: https://oeis.org/A191624

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A191624
Largest prime factor of n^n - n^(n-1) - n^(n-2) - ... - n^2 - n - 1.
1
7, 19, 293, 1493, 179, 1091, 10593529, 379721, 165664841, 66987982331, 240717199, 28048051, 133933781, 25506609089573701, 107140256350247, 793435901761, 268232479553269300213, 4075297, 3063504618316968426599, 1372263056872621, 7514001866134191512025247
OFFSET
3,1
LINKS
Daniel Suteu and Harvey P. Dale, Table of n, a(n) for n = 3..72 (terms 3..52 from Harvey P. Dale)
FORMULA
a(n) = A006530(A191690(n)).
MAPLE
A006530 := proc(n) max ( numtheory[factorset](n) ) ; end proc:
A191690 := proc(n) n^n-add( n^j, j=0..n-1) ; end proc:
A191624 := proc(n) A006530(A191690(n)) ; end proc:
seq(A191624(n), n=3..15) ; # R. J. Mathar, Jun 23 2011
MATHEMATICA
Table[With[{s=n^Range[0, n]}, FactorInteger[Last[s]-Total[Most[s]]][[-1, 1]]], {n, 3, 20}] (* Harvey P. Dale, Feb 02 2015 *)
PROG
(PARI) a(n) = if(n==0, return(1)); vecmax(factor(n^n - (n^n-1)/(n-1))[, 1]); \\ Daniel Suteu, Jun 09 2022
CROSSREFS
Sequence in context: A201479 A228150 A331404 * A221740 A364572 A394098
KEYWORD
nonn
AUTHOR
EXTENSIONS
More terms from Harvey P. Dale, Feb 02 2015
STATUS
approved