A104037 Numbers of primes between two sexy primes.

1, 1, 1, 1, 1, 0, 0, 1, 1, 0, 0, 0, 1, 0, 0, 1, 1, 1, 1, 0, 0, 0, 0, 0, 1, 1, 1, 1, 0, 0, 0, 0, 0, 1, 1, 1, 0, 1, 0, 0, 0, 0, 0, 0, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 1, 1

Offset: 1

Author

Giovanni Teofilatto, Mar 31 2005

Keywords

• easy
• nonn

Links

• Robert Israel, Table of n, a(n) for n = 1..10000
• Eric Weisstein's World of Mathematics, Sexy Primes. [The definition in this webpage is unsatisfactory, because it defines a "sexy prime" as a pair of primes.- _N. J. A. Sloane_, Mar 07 2021].

Crossrefs

Cf. A023201 (sexy primes), A046117.

Programs

Maple

p:=1: q:= 0: r:= 1: s:= 1: count:= 0: Res:= NULL:
while count < 100 do
  t:= charfcn[{true}](isprime(p+6));
  if t=1 and q=1 then
     count:= count + 1;
     Res:= Res, r+s;
  fi;
  p:= p+2;
  q:= r; r:= s; s:= t;
od:
Res; # Robert Israel, Jun 23 2019

Extensions

Corrected and extended by Robert Israel, Jun 23 2019