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 A242484 Numbers n such that antisigma(n) mod n = 0, where antisigma(n) = A024816(n) = sum of numbers less than n which do not divide n. 6
 1, 2, 24, 4320, 4680, 26208, 8910720, 17428320, 20427264, 91963648, 197064960, 8583644160, 10200236032, 21857648640, 57575890944, 57629644800, 206166804480, 17116004505600, 1416963251404800, 15338300494970880 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS Numbers n such that antisigma(n) mod n = A229110(n) = 0. If there are any odd multiply-perfect numbers, they are members of this sequence. If there is no odd multiply-perfect number, then a(n) = A159907(n-1) for n >= 2. LINKS Table of n, a(n) for n=1..20. EXAMPLE 24 is in sequence because antisigma(24) mod 24 = 240 mod 24 = 0. PROG (Magma) [n: n in [1..1000000] | 0 eq ((n*(n+1))div 2 - SumOfDivisors(n)) mod n] CROSSREFS Cf. A242480, A242481, A242482, A242483, A242485, A242486. Sequence in context: A059332 A000794 A159907 * A088912 A342573 A203465 Adjacent sequences: A242481 A242482 A242483 * A242485 A242486 A242487 KEYWORD nonn AUTHOR Jaroslav Krizek, May 16 2014 STATUS approved

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Last modified June 20 10:31 EDT 2024. Contains 373516 sequences. (Running on oeis4.)