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A139236
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Second differences of even superperfect numbers A061652.
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10
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OFFSET
| 1,1
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COMMENTS
| Second differences of Mersenne primes A000668, divided by 2 (see A139232).
Also, second differences of superperfect numbers A019279, if there are no odd superperfect numbers.
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FORMULA
| a(n) = A139234(n+1) - A139234(n).
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CROSSREFS
| Cf. A000668, A019279, A061652, A139228, A139229, A139230, A139231, A139232, A139233, A139234, A139235, A139237.
Sequence in context: A117404 A089222 A139242 * A096000 A047672 A200872
Adjacent sequences: A139233 A139234 A139235 * A139237 A139238 A139239
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KEYWORD
| nonn
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AUTHOR
| Omar E. Pol (info(AT)polprimos.com), Apr 18 2008
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