login

Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 61st year, we have over 378,000 sequences, and we’ve reached 11,000 citations (which often say “discovered thanks to the OEIS”).

A071557
Numbers k such that A065876(k) = k^2-k+1.
3
0, 2, 3, 4, 5, 6, 7, 9, 10, 11, 14, 15, 16, 19, 20, 24, 25, 26, 29, 35, 36, 39, 40, 41, 45, 49, 51, 54, 56, 59, 61, 65, 66, 69, 71, 74, 79, 84, 85, 90, 94, 95, 101, 110, 116, 120, 121, 124, 126, 130, 131, 134, 139, 141, 145, 146, 150, 156, 159, 160, 165, 169, 170, 171
OFFSET
1,2
LINKS
MATHEMATICA
q[n_] := Module[{m = n+1}, While[!Divisible[m^2 + 1, n^2 + 1], m++]; m == n^2 - n + 1]; Select[Range[200], q] (* Amiram Eldar, May 05 2022 *)
PROG
(PARI) for(n=0, 300, q=n+1; while((q^2+1)%(n^2+1)>0, q++); if(q==n^2-n+1, print1(n, ", ")))
CROSSREFS
Cf. A065876.
Sequence in context: A174328 A272570 A123101 * A331802 A378896 A271108
KEYWORD
easy,nonn
AUTHOR
Benoit Cloitre, May 30 2002
EXTENSIONS
a(1) = 0 added by Amiram Eldar, May 05 2022
STATUS
approved