1,1

First differences of Mersenne primes A000668, divided by 2 (See A139231).

Also, first differences of superperfect numbers A019279, if there are no odd superperfect numbers.

O. E. Pol, Determinacion geometrica de los numeros primos y perfectos".

a(n) = A061652(n+1) - A061652(n) = A139231(n)/2. Also, a(n) = A019279(n+1) - A019279(n), if there are no odd superperfect numbers.

a(2)=12 because A061652(2)=4 and A061652(3)=16 then 16-4 = 12.

Cf. A000668, A019279, A061652, A139228, A139229, A139230, A139231, A139232, A139233, A139235, A139236, A139237.

Sequence in context: A060238 A085495 A119978 this_sequence A039784 A028243 A003493

Adjacent sequences: A139231 A139232 A139233 this_sequence A139235 A139236 A139237

nonn

Omar E. Pol (info(AT)polprimos.com), Apr 18 2008