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Search: id:A135651
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| A135651 |
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Even superperfect numbers written in base 2. |
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+0
2
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| 10, 100, 10000, 1000000, 1000000000000, 10000000000000000, 1000000000000000000, 1000000000000000000000000000000
(list; graph; listen)
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OFFSET
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1,1
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COMMENT
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Also, superperfect numbers (A019279) written in base 2 (If there are no odd perfect numbers).
Also, concatenation of "1" and A090748(n) digits "0".
The number of digits of a(n) is equal to A000043(n) and also equal to the number of digits of n-th Mersenne prime written in base 2 (See A117293, A135650).
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EXAMPLE
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a(3)=10000 because the 3rd even superperfect number A061652(3)=16 and 16 written in base 2 is equal to 10000.
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CROSSREFS
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Cf. A000043, A000668, A019279, A061652, A090748, A117293, A135650.
Sequence in context: A164832 A144822 A097178 this_sequence A139103 A067217 A066327
Adjacent sequences: A135648 A135649 A135650 this_sequence A135652 A135653 A135654
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KEYWORD
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base,nonn
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AUTHOR
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Omar E. Pol (info(AT)polprimos.com), Feb 23 2008
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