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 A107924 Even numbers n such that n^2 is an arithmetic number. 5
 296, 536, 632, 872, 1208, 1304, 1544, 2072, 2216, 2648, 2984, 3584, 3656, 3752, 3848, 3896, 3904, 3992, 4328, 4424, 4568, 4904, 5624, 5672, 5912, 6008, 6104, 6584, 6968, 7016, 7256, 7352, 7928, 8216, 8264, 8456, 8696, 8896, 8936, 9032, 9128, 9176, 9368 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Odd numbers with this property are much more numerous, cf. A107925, A003601 (arithmetic number). LINKS R. J. Mathar, Michael De Vlieger, Table of n, a(n) for n = 1..10778 (first 443 terms from R. J. Mathar) MAPLE isA107924 := proc(n) if type(n, 'even') then dvs := numtheory[divisors](n^2) ; add(d, d=dvs)/nops(dvs) ; if type(%, 'integer') then true; else false; end if; else false; end if; end proc: n := 1 : for k from 2 to 100000 do if isA107924(k) then printf("%d %d\n", n, k) ; n := n+1 ; end if; end do: # create b-file, R. J. Mathar, Jul 28 2014 MATHEMATICA Select[Range[2, 10000, 2], Mod[DivisorSigma[1, #^2], DivisorSigma[0, #^2]]==0&] CROSSREFS Cf. A003601, A107925. Sequence in context: A003780 A338592 A206339 * A224170 A223861 A223984 Adjacent sequences: A107921 A107922 A107923 * A107925 A107926 A107927 KEYWORD nonn,easy AUTHOR Zak Seidov, Jun 10 2005 STATUS approved

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Last modified September 15 19:46 EDT 2024. Contains 375954 sequences. (Running on oeis4.)