A067784 Numbers k such that prime(k+1)^4 == prime(k)^4 (mod k).

1, 2, 3, 4, 5, 6, 8, 10, 12, 15, 16, 20, 24, 29, 30, 40, 45, 48, 56, 60, 64, 65, 80, 92, 105, 111, 120, 144, 146, 160, 180, 182, 212, 232, 240, 246, 336, 340, 344, 348, 360, 376, 439, 470, 476, 580, 624, 680, 709, 819, 832, 914, 984, 1020, 1058, 1290, 1341, 1352

Offset

1,2

Links

Robert Israel, Table of n, a(n) for n = 1..300

Maple

q:= 2: count:= 0:
for n from 1 while count < 100 do
  p:= q; q:= nextprime(p);
  if q^4 - p^4 mod n = 0 then count:= count+1; A[count]:= n; fi;
od:
seq(A[i], i=1..count); # Robert Israel, May 16 2017

Mathematica

Select[Range[100], Mod[Prime[# + 1]^4 , #] == Mod[Prime[#]^4, #] &] (* G. C. Greubel, May 17 2017 *)

Crossrefs

Cf. A030514, A067785.

Sequence in context: A336505 A303704 A067939 * A324107 A018744 A018478

Adjacent sequences: A067781 A067782 A067783 * A067785 A067786 A067787

Keyword

nonn

Author

Benoit Cloitre, Feb 06 2002

Status

approved