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 A097464 5-infinitary perfect numbers: n such that 5-infinitary-sigma(n)=2*n. 1
 6, 28, 496, 47520, 288288, 308474880 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Here 5-infinitary-sigma(a) means sum of 5-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 5-ary expansion everywhere that the corresponding r_i has a digit b, then d is a 5-infinitary-divisor of n. Is it certain that 308474880 is the 6th term? M. F. Hasler, Nov 20 2010 LINKS FORMULA {n: A097863(n) = 2*n}. EXAMPLE Factorizations: 2*3, 2^2*7, 2^4*31, 2^5*3^3*5*11, 2^5*3^2*7*11*13, 2^10*3*5*7*19*151 CROSSREFS Cf. A074849. Sequence in context: A000396 A152953 A066239 * A166998 A038182 A095723 Adjacent sequences:  A097461 A097462 A097463 * A097465 A097466 A097467 KEYWORD nonn AUTHOR EXTENSIONS Missing a(4) inserted by R. J. Mathar, Nov 20 2010 STATUS approved

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Last modified October 18 03:25 EDT 2019. Contains 328135 sequences. (Running on oeis4.)