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 A328860 Numbers that are 4-imperfect. 1
 993803899780063855042560, 2028353759451110328141864960, 6476620014866676143312363520 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 LINKS Table of n, a(n) for n=1..3. Douglas E. Iannucci, On a variation of perfect numbers, INTEGERS: Electronic Journal of Combinatorial Number Theory, 6 (2006), #A41. Andrew Lelechenko, 4-imperfect numbers, Apr 19 2014. Michel Marcus, More 4-imperfect numbers, Nov 07 2017. Michel Marcus, solveIMP PARI script Michel Marcus, List of 4-imperfect numbers (including the 2 files above), last edit Jun 2019. Weiyi Zhou and Long Zhu, On k-imperfect numbers, INTEGERS: Electronic Journal of Combinatorial Number Theory, 9 (2009), #A01. PROG (PARI) solveIMP(1, 4, 10^24) CROSSREFS Cf. A127724 (k-imperfect), A127725 (2-imperfect), A127726 (3-imperfect). Cf. A309806 (the k values). Cf. A206369 (the rho function). Sequence in context: A003806 A257374 A217422 * A095442 A332605 A130682 Adjacent sequences: A328857 A328858 A328859 * A328861 A328862 A328863 KEYWORD nonn,more,bref AUTHOR Michel Marcus, Feb 16 2020 STATUS approved

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Last modified June 13 22:21 EDT 2024. Contains 373391 sequences. (Running on oeis4.)