A301346 Largest prime factor of A020549(n) = (n!)^2 + 1.

2, 2, 5, 37, 577, 14401, 39877, 251501, 95629553, 131681894401, 13168189440001, 1593350922240001, 2271708245569901, 38775788043632640001, 2404319663572286441, 1272170577304043929, 2938007628841577533852349, 13980942259426143240713449, 1107848353183710355135404972973, 20831587158104092560535861261

Offset: 0

Author

Seiichi Manyama, Mar 19 2018

Keywords

• nonn

Comments

a(n) = A020549(n) for n in A046029.

Links

• Daniel Suteu, Table of n, a(n) for n = 0..70

Crossrefs

Cf. A002583, A020549, A046029, A282706.

Programs

Maple

a:= n-> max(numtheory[factorset](n!^2+1)):
seq(a(n), n=0..20);  # Alois P. Heinz, Mar 19 2018

PARI

a(n) = vecmax(factor(n!^2 + 1)[,1]); \\ Daniel Suteu, Jun 10 2022

Formula

a(n) = A006530(A020549(n)). - Altug Alkan, Mar 19 2018