A146315 - OEIS

%I #5 Jul 03 2016 00:17:34

%S 2,7,11,13,23,29,31,47,53,59,61,79,83,89,97,127,131,137,139,167,173,

%T 179,191,193,223,227,233,239,251,293,307,311,313,317,359,383,389,397,

%U 439,443,461,467,479,547,557,563,569,571,647,653,659,673,727,743,761,773

%N Prime differences of primes subtracted from nearest square

%C Terms in A146315 + A146316 produce a square

%F {p in A000040: A068527(p) in A000040}. - R. J. Mathar, Sep 26 2011

%e a(6)=29 because when the prime 29 is subtracted from the square 36, the result is another prime, 7

%o (UBASIC) 10 'sq less pr are prime 20 N=1:O=1:C=1 30 A=3:S=sqrt(N) 40 B=N\A 50 if B*A=N then 120 60 A=A+2 70 if A<=S then 40 80 R=O^2:Q=R-N 90 if N<R and N=prmdiv(N) and Q=prmdiv(Q) then print R;N;Q:N=N+2:C=C+1:goto 30 100 if C>31 then stop 120 N=N+2:if N<R then 30:else O=O+1:goto 80

%Y Cf. A146316 - A146318.

%K easy,nonn

%O 1,1

%A _Enoch Haga_, Oct 30 2008