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A139229
First differences of perfect numbers A000396, divided by 2.
11
11, 234, 3816, 16771104, 4278159360, 64424411136, 1152921435350630400, 1329227995784915871174424803906945024, 95780971304118052318168693257235946738152352797163520
OFFSET
1,1
LINKS
FORMULA
a(n) = A139228(n)/2.
MATHEMATICA
Differences[Select[Range[10000], DivisorSigma[1, #] == 2# &]]/2 (* Alonso del Arte, Mar 05 2020 *)
Differences[PerfectNumber[Range[12]]]/2 (* Paolo Xausa, Oct 20 2023 *)
KEYWORD
nonn
AUTHOR
Omar E. Pol, Apr 19 2008
EXTENSIONS
a(6)-a(9) from A139228(n)/2 by Jinyuan Wang, Mar 04 2020
STATUS
approved