This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
// See Links section in A116893.
for(n = 1, 10^9, my(x = gcd(n! + 1, n^n + 1)); if(x != 1 && x != 2*n + 1, print1(x, ", ")))
gcd(1!+1, 1^1+1) = 2, gcd(2!+1, 2^2+1) = 1 and gcd(3!+1, 3^3+1) = 7, so 1 and 3 are the first two terms of the sequence.
See Links section.
Select[Range[1500], (GCD[ #!+1, #^#+1] > 1)&]
isok(n) = gcd(n! + 1, n^n + 1) != 1; \\ Michel Marcus, Jul 22 2018
a(3) = gcd(3! + 1, 3^3 + 1) = gcd(7,28) = 7.
Table[GCD[n! + 1, n^n + 1], {n, 101}] (* Robert G. Wilson v, Mar 09 2006 *)
A116891(n) = gcd(n!+1,(n^n)+1); \\ Antti Karttunen, Jul 22 2018
gcd(1!+1,1^1+1) = 2 gives the first term; gcd(3!+1,3^3+1) = gcd(7,28) = 7 gives the second, and so on.
See Links section in A116893.
f[n_] := GCD[n! + 1, n^n + 1]; t = Array[f, 1295]; Rest@ Union@ t (* Robert G. Wilson v, Mar 09 2006 *)
lista(nn) = for (n=1, nn, if ((g=gcd(n! + 1, n^n + 1)) != 1, print1(g, ", "))); \\ Michel Marcus, Jul 22 2018
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