OFFSET
1,1
COMMENTS
Contains A002145 as a subsequence.
Numbers that are divisible by 4 or by a term of A002145. - Robert Israel, May 14 2020
LINKS
Robert Israel, Table of n, a(n) for n = 1..10000
MAPLE
filter:= n -> n mod 4 = 0 or member(3, numtheory:-factorset(n) mod 4):
select(filter, [$1..1000]); # Robert Israel, May 14 2020
MATHEMATICA
Table[If[Reduce[x^2==-1, Modulus->n]===False, n], {n, 2, 200}]//Union
PROG
(PARI) for(n=1, 1e3, if(!issquare(Mod(-1, n)), print1(n", "))) \\ Charles R Greathouse IV, Jul 04 2011
CROSSREFS
KEYWORD
nonn
AUTHOR
José María Grau Ribas, Jul 01 2011
STATUS
approved