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A074849
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4-infinitary perfect numbers: n such that 4-infinitary-sigma(n)=2*n.
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1
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OFFSET
| 0,1
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COMMENTS
| Here 4-infinitary-sigma(a) means sum of 4-infinitary-divisor of a. If n=Product p(i)^r(i) and d=Product p(i)^s(i), each s(i) has a digit a<=b in its 4-ary expansion everywhere that the corresponding r(i) has a digit b, then d is a 4-infinitary-divisor of n.
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EXAMPLE
| Factorizations: 2*3, 2^2*7, 2^4*3^3*5*17, 2^4*3^2*7*13*17, 2^5*3^4*7*17*41, 2^8*3^2*7*13^2*31*61, 2^12*3^5*7*11*41*43*257.
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CROSSREFS
| Sequence in context: A095723 A057246 A154895 * A189373 A100874 A156927
Adjacent sequences: A074846 A074847 A074848 * A074850 A074851 A074852
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KEYWORD
| nonn
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AUTHOR
| Yasutoshi Kohmoto (zbi74583(AT)boat.zero.ad.jp), Sep 10 2002
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