OFFSET
1,1
COMMENTS
Primes n such that n!*B(n+1) is an integer where B(k) are the Bernoulli numbers.
All primes except for the lower members of twin primes - i.e. remove 3, 5, 11, 17, 29, 41, 59, 71, 101, 107, 137, ... - Gerard Schildberger, Feb 13 2005
LINKS
T. D. Noe, Table of n, a(n) for n = 1..1000
FORMULA
Except for a(1)=2, a(n+1)=A049591(n).
a(n) ~ n log n. - Charles R Greathouse IV, Jul 01 2013
MATHEMATICA
f[n_]:=PrimeQ[n+2]; lst={}; Do[p=Prime[n]; If[ !f[p], AppendTo[lst, p]], {n, 5!}]; lst (* Vladimir Joseph Stephan Orlovsky, Oct 17 2009 *)
PROG
(Magma) [p: p in PrimesUpTo(400) | NextPrime(p)-p ne 2]; // Bruno Berselli, Apr 09 2013
(PARI) is(n)=isprime(n)&&!isprime(n+2) \\ Charles R Greathouse IV, Jul 01 2013
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Benoit Cloitre, Feb 06 2002
EXTENSIONS
Better description from Vladeta Jovovic, Dec 14 2002
STATUS
approved