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A185961
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Let d_1=1 < d_2 < d_3 < ... be the divisors of n; sequence lists positive numbers n such that for some k, n = 2(d_1 + ... + d_k).
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1
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2, 6, 12, 28, 40, 48, 224, 234, 496, 960, 8128, 47616, 174592, 10371840, 15037440, 28090368, 33550336, 134209536, 207516672, 492101632, 1150402560, 8589869056, 59205411720, 137438691328
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OFFSET
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1,1
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REFERENCES
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Arie Groeneveld, Posting to Sequence Fans Mailing List, Feb 06, 2011
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LINKS
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PROG
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(PARI) forstep(n=2, 33550336, 2, d=divisors(n); s=0; for(j=1, numdiv(n), s=s+2*d[j]; if(s>=n, if(s==n, print1(n ", ")); next(2)))) \\ Donovan Johnson, Jan 24 2014
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CROSSREFS
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KEYWORD
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nonn,more
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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