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A104370 Sum of divisors of A104365(n) = A104350(n) + 1. 8

%I #24 Apr 15 2023 14:13:58

%S 3,4,8,14,62,182,1372,2522,7562,38272,415802,1247402,16313472,

%T 114107904,570257104,1161216000,21043021824,57893308852,1099944846002,

%U 5530978026000,39437046917604,425165932107504,10235889009520064,29233062045242352,146100174169950002,1917846796927501440,5805987050510562240,39918123659008838880

%N Sum of divisors of A104365(n) = A104350(n) + 1.

%H Max Alekseyev, <a href="/A104370/b104370.txt">Table of n, a(n) for n = 1..158</a> (terms 1..76 terms from Amiram Eldar, terms 142..151 from Tyler Busby)

%H Reinhard Zumkeller, <a href="/A104350/a104350.txt">Products of largest prime factors of numbers <= n</a>

%F a(n) = A000203(A104365(n)).

%t a[n_] := DivisorSigma[1, 1 + Product[FactorInteger[k][[-1, 1]], {k, 1, n}]]; Array[a, 30] (* _Amiram Eldar_, Feb 12 2020 *)

%Y Cf. A000203, A104350, A104362, A104365, A104366, A104367, A104368, A104369, A104371, A104372.

%K nonn

%O 1,1

%A _Reinhard Zumkeller_, Mar 06 2005

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Last modified March 29 08:53 EDT 2024. Contains 371268 sequences. (Running on oeis4.)