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A139233
Second differences of perfect numbers
A000396
, divided by 2.
11
223, 3582, 16767288, 4261388256, 60146251776, 1152921370926219264, 1329227995784915870021503368556314624, 95780971304118050988940697472320075563727548890218496
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OFFSET
1,1
LINKS
Paolo Xausa,
Table of n, a(n) for n = 1..13
FORMULA
a(n) =
A139230
(n)/2.
MATHEMATICA
Differences[PerfectNumber[Range[12]], 2]/2 (*
Paolo Xausa
, Oct 20 2023 *)
CROSSREFS
Cf.
A000396
,
A139228
,
A139229
,
A139230
,
A139231
,
A139232
,
A139234
,
A139235
,
A139236
,
A139237
.
Sequence in context:
A205273
A205266
A152834
*
A205265
A153165
A094491
Adjacent sequences:
A139230
A139231
A139232
*
A139234
A139235
A139236
KEYWORD
nonn
AUTHOR
Omar E. Pol
, Apr 19 2008
EXTENSIONS
a(5)-a(8) from
Jinyuan Wang
, Mar 04 2020
STATUS
approved
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Last modified March 28 05:39 EDT 2024. Contains 371235 sequences. (Running on oeis4.)