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A139237
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Second differences of even superperfect numbers A061652, divided by 2.
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12
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OFFSET
| 1,1
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COMMENTS
| Second differences of Mersenne primes A000668, divided by 4 (see A139232).
Also, second differences of superperfect numbers A019279, divided by 2, if there are no odd superperfect numbers.
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FORMULA
| a(n) = A139236(n)/2.
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CROSSREFS
| Cf. A000668, A019279, A061652, A139228, A139229, A139230, A139231, A139232, A139233, A139234, A139235, A139236.
Sequence in context: A091059 A203180 A139243 * A089082 A106229 A129734
Adjacent sequences: A139234 A139235 A139236 * A139238 A139239 A139240
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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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