This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A139235 #19 Mar 14 2024 18:12:05 %S A139235 1,6,24,2016,30720,98304,536739840,576460751766552576, %T A139235 154742504334211782058967040,40564664464798430175360140181504, %U A139235 42535255300298100629580978034468454400 %N A139235 First differences of even superperfect numbers A061652, divided by 2. %C A139235 First differences of Mersenne primes A000668, divided by 4 (see A139231). %C A139235 Also, first differences of superperfect numbers A019279, divided by 2, if there are no odd superperfect numbers. %H A139235 Paolo Xausa, <a href="/A139235/b139235.txt">Table of n, a(n) for n = 1..17</a> %F A139235 a(n) = A139234(n)/2. %t A139235 Differences[2^MersennePrimeExponent[Range[14]]-1]/4 (* _Paolo Xausa_, Oct 20 2023 *) %Y A139235 Cf. A000668, A019279, A061652, A139228, A139229, A139230, A139231, A139232, A139233, A139234, A139236, A139237. %K A139235 nonn %O A139235 1,2 %A A139235 _Omar E. Pol_, Apr 18 2008 %E A139235 a(8)-a(11) from _Jinyuan Wang_, Mar 04 2020