A096264 Primes that do not divide any terms of the sequence f given by f(1) = 2, f(n+1) = f(n)^2-f(n)+1.

5, 11, 17, 19, 23, 29, 31, 37, 41, 47, 53, 59, 61, 67, 71, 79, 83, 89, 97, 101, 103, 107, 109, 113, 127, 131, 137, 149, 151, 157, 163, 167, 173, 179, 191, 193, 197, 199, 211, 223, 227, 229, 233, 239, 241, 251, 257, 263, 269, 271, 277, 281, 283

Offset: 1

Author

Jeffrey Shallit, Aug 04 2004

Keywords

• nonn

Links

• Jinyuan Wang, Table of n, a(n) for n = 1..5000
• R. W. K. Odoni, On the prime divisors of the sequence w_{n+1} = 1+w_1 ... w_n, J. London Math. Soc. 32 (1985), 1-11.

Crossrefs

Complement of A007996 (in the primes).

Programs

Maple

IsSylvester:=proc(p)
local x,S ;x:=2 : S:=NULL: while not member(x, [S]) do if x=0 then
return(true) fi; S := S ,x; x := (x^2-x+1) mod p od : return false end:
L:=NULL:p:=5:while p<1000 do if not IsSylvester(p) then L:=L,p fi : p:=nextprime(p) od:
L;
# Robert FERREOL, Feb 14 2019

Extensions

Definition corrected (following a remark by Don Reble) by M. F. Hasler, Apr 24 2014