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A139234
First differences of even superperfect numbers A061652.
10
2, 12, 48, 4032, 61440, 196608, 1073479680, 1152921503533105152, 309485008668423564117934080, 81129328929596860350720280363008, 85070510600596201259161956068936908800
OFFSET
1,1
COMMENTS
First differences of Mersenne primes A000668, divided by 2 (see A139231).
Also, first differences of superperfect numbers A019279, if there are no odd superperfect numbers.
FORMULA
a(n) = A061652(n+1) - A061652(n) = A139231(n)/2. Also, a(n) = A019279(n+1) - A019279(n), if there are no odd superperfect numbers.
EXAMPLE
a(2) = 12 because A061652(2) = 4 and A061652(3) = 16 then 16 - 4 = 12.
MATHEMATICA
Differences[Table[2^(MersennePrimeExponent[n]-1), {n, 12}]] (* Requires Mathematica version 10 or later *) (* Harvey P. Dale, Aug 18 2020 *)
KEYWORD
nonn
AUTHOR
Omar E. Pol, Apr 18 2008
EXTENSIONS
a(8)-a(11) from A139231(n)/2 by Jinyuan Wang, Mar 04 2020
STATUS
approved