A067690 gcd((2n)!+1, n!+1) when not equal to 1.

7, 11, 61, 19, 43, 47, 67, 79, 103, 127, 131, 163, 179, 191, 199, 227, 263, 347, 367, 383, 419, 431, 443, 479, 491, 503, 523, 563, 571, 599, 607, 619, 631, 683, 691, 727, 739, 743, 787, 823, 839, 863, 887, 947, 991, 1019, 1051, 1087, 1091, 1123, 1151

Offset

1,1

Links

Harvey P. Dale, Table of n, a(n) for n = 1..1500

Mathematica

a[n_] := GCD[(2n)! + 1, n! + 1]; Select[ Table[ a[n], {n, 1, 1000}], # != 1 &] (* Jean-François Alcover, Dec 16 2011 *)
Table[GCD[(2n)!+1, n!+1], {n, 700}]/.(1->Nothing) (* Harvey P. Dale, Jan 12 2020 *)

Crossrefs

Sequence in context: A263231 A077411 A085016 * A358585 A196181 A177182

Adjacent sequences: A067687 A067688 A067689 * A067691 A067692 A067693

Keyword

nonn,nice

Author

Benoit Cloitre, Feb 04 2002

Status

approved