OFFSET
0,1
COMMENTS
The larger terms (conjectured: records) are those whose indices are listed in A099350.
LINKS
Chai Wah Wu, Table of n, a(n) for n = 0..92 (n = 0..60 from Vincenzo Librandi)
MATHEMATICA
Table[FactorInteger[4 n! - 1][[1, 1]], {n, 0, 45}] (* Michael De Vlieger, Sep 21 2015 *)
PROG
(PARI) a(n)=A020639(n!*4-1)
(PARI) a(n) = factor(4*n!-1)[1, 1] \\ Michel Marcus, Sep 20 2015
(Magma) [PrimeDivisors(4*Factorial(n)-1)[1]: n in [0..50]]; // Bruno Berselli, Sep 21 2015
CROSSREFS
KEYWORD
nonn
AUTHOR
M. F. Hasler, Sep 20 2015
STATUS
approved