A139288 - OEIS

%I #6 Jun 21 2021 12:07:21

%S 4,16,256,4096,1048576,16777216,4294967296,68719476736,17592186044416,

%T 72057594037927936,1152921504606846976,4722366482869645213696,

%U 1208925819614629174706176,19342813113834066795298816

%N 2^(2p - 1)/2, where p is prime.

%F a(n)=A139286(n)/2.

%t Table[2^(2p-1)/2,{p,Prime[Range[20]]}] (* _Harvey P. Dale_, Jun 21 2021 *)

%Y Cf. A139286, A139287, A139289, A139290, A139291, A139292, A139293, A139294, A139306.

%K nonn

%O 1,1

%A _Omar E. Pol_, Apr 13 2008

%E More terms from _Jon E. Schoenfield_, Jul 16 2010