OFFSET
1,1
COMMENTS
LINKS
Robert Israel, Table of n, a(n) for n = 1..10000
EXAMPLE
n=10; n+1=11; 121-100=21; 21 is not a square nor a prime.
MAPLE
remove(n -> issqr(2*n+1) or isprime(2*n+1), [$1..1000]); # Robert Israel, Jun 16 2017
MATHEMATICA
Select[Range[200], ! PrimeQ[2 # + 1] && ! IntegerQ[Sqrt[2 # + 1]] &] (* T. D. Noe, Jun 13 2013 *)
CROSSREFS
KEYWORD
nonn
AUTHOR
César Aguilera, Jun 13 2013
STATUS
approved