A080713 - OEIS

%I #5 Nov 01 2017 16:55:49

%S 1,2,3,4,5,8,10,13,18,19,24,25,29,31,34,37,39,43,49,53,55,58,59,61,64,

%T 67,69,73,74,79,81,85,89,91,94,95,97,99,100,103,109,115,119,121,125,

%U 127,129,130,133,137,139,142,145,147,149,151,154,157,159,163,165,169,170

%N Numbers not of the form p + q^2.

%H Charles R Greathouse IV, <a href="/A080713/b080713.txt">Table of n, a(n) for n = 1..10000</a>

%t Complement[ Table[k, {k, 1, 200}], Take[ Union[ Flatten[ Table[ Prime[i] + Prime[j]^2, {i, 1, 80}, {j, 1, 10}]]], 250]]

%o (PARI) is(n)=if(n%2, !isprime(n-4) && isprimepower(n-2)!=2, forprime(q=3, sqrtint(n), if(isprime(n-q^2), return(0))); n!=6) \\ _Charles R Greathouse IV_, Oct 25 2017

%Y Complement of A081053.

%K nonn

%O 1,2

%A _Robert G. Wilson v_, Mar 05 2003