A256344 Moduli n for which A248218(n) = 4 (length of the terminating cycle of 0 under x -> x^2+1 modulo n).

13, 26, 39, 47, 52, 78, 79, 91, 94, 104, 113, 141, 143, 156, 158, 169, 173, 182, 188, 197, 208, 226, 237, 247, 273, 282, 286, 299, 312, 316, 329, 338, 339, 346, 353, 364, 376, 377, 394, 403, 416, 429, 439, 452, 474, 481, 494, 507, 517, 519, 546, 553, 559, 564, 572, 591, 598

Offset

1,1

Comments

If x is a member and y is a member of this sequence or A248219 or A256342, then LCM(x,y) is a member. - Robert Israel, Mar 09 2021

Links

Robert Israel, Table of n, a(n) for n = 1..10000

Example

See A256342 or A256349.

Maple

filter:= proc(n) local x, k, R, p;
  x:= 0; R[0]:= 0;
  for k from 1 do
    x:= x^2+1 mod n;
    if assigned(R[x]) then return evalb(k-R[x] = 4)
    else R[x]:= k
    fi
  od;
end proc:
select(filter, [$1..1000]); # Robert Israel, Mar 09 2021

Prog

(PARI) for(i=1, 600, A248218(i)==4&&print1(i", "))

Crossrefs

Cf. A248218, A248219, A256342 - A256349, A003095, A247981.

Sequence in context: A101870 A321714 A260748 * A044853 A044898 A048842

Adjacent sequences: A256341 A256342 A256343 * A256345 A256346 A256347

Keyword

nonn

Author

M. F. Hasler, Mar 25 2015

Status

approved