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 A096821 Solutions to Mod[sigma(x),x]=12 of the form p*(p+13)/2 where p is a prime of form=2^j-13, of which j exponents are listed in A096818. 1
 24, 304, 127744, 33501184, 8589082624, 10384593717069654320312270165377024, 822752278660603021077484591278411581166520461101278617407586304, 15177100720513508366558296147058741458142670970377727126573378340391656803557965824 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS The relevant A084306 includes additional solution like 21, while A076496 contains solutions of 6k form too. LINKS F. Firoozbakht, M. F. Hasler, Variations on Euclid's formula for Perfect Numbers, JIS 13 (2010) #10.3.1. EXAMPLE 8th term is (2^136)*(-13+2^137) with 83 decimal digits; n=4: a[4]=(2^3)*(16-13)=24; CROSSREFS Cf. A084306, A096518, A000203, A076496. Sequence in context: A171742 A187851 A125436 * A168303 A053215 A290939 Adjacent sequences:  A096818 A096819 A096820 * A096822 A096823 A096824 KEYWORD nonn AUTHOR Labos Elemer, Jul 13 2004 STATUS approved

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Last modified December 1 22:12 EST 2021. Contains 349435 sequences. (Running on oeis4.)