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%I #14 Oct 20 2023 08:40:18
%S 11,234,3816,16771104,4278159360,64424411136,1152921435350630400,
%T 1329227995784915871174424803906945024,
%U 95780971304118052318168693257235946738152352797163520
%N First differences of perfect numbers A000396, divided by 2.
%H Paolo Xausa, <a href="/A139229/b139229.txt">Table of n, a(n) for n = 1..14</a>
%F a(n) = A139228(n)/2.
%t Differences[Select[Range[10000], DivisorSigma[1, #] == 2# &]]/2 (* _Alonso del Arte_, Mar 05 2020 *)
%t Differences[PerfectNumber[Range[12]]]/2 (* _Paolo Xausa_, Oct 20 2023 *)
%Y Cf. A000396, A139228, A139230, A139231, A139232, A139233, A139234, A139235, A139236, A139237.
%K nonn
%O 1,1
%A _Omar E. Pol_, Apr 19 2008
%E a(6)-a(9) from A139228(n)/2 by _Jinyuan Wang_, Mar 04 2020