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A139230 Second differences of perfect numbers A000396. 11
446, 7164, 33534576, 8522776512, 120292503552, 2305842741852438528, 2658455991569831740043006737112629248, 191561942608236101977881394944640151127455097780436992 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
LINKS
Paolo Xausa, Table of n, a(n) for n = 1..13
FORMULA
a(n) = A139228(n+1) - A139228(n). - Jinyuan Wang, Mar 04 2020
MATHEMATICA
Differences[PerfectNumber[Range[12]], 2] (* Paolo Xausa, Oct 20 2023 *)
CROSSREFS
Cf. A000396, A139228, A139229, A139231, A139232, A139233, A139234, A139235, A139236, A139237.
Sequence in context: A340151 A025354 A025346 * A221506 A065576 A200071
Adjacent sequences: A139227 A139228 A139229 * A139231 A139232 A139233
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 August 18 19:26 EDT 2024. Contains 375273 sequences. (Running on oeis4.)