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A104370 Sum of divisors of A104350(n) + 1. 4
3, 4, 8, 14, 62, 182, 1372, 2522, 7562, 38272, 415802, 1247402, 16313472, 114107904, 570257104, 1161216000, 21043021824, 57893308852, 1099944846002, 5530978026000, 39437046917604, 425165932107504, 10235889009520064 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Amiram Eldar, Table of n, a(n) for n = 1..76

Reinhard Zumkeller, Products of largest prime factors of numbers <= n

FORMULA

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

MATHEMATICA

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

CROSSREFS

Cf. A000203, A104350, A104369, A104362.

Sequence in context: A026632 A332985 A026654 * A310013 A033854 A042981

Adjacent sequences:  A104367 A104368 A104369 * A104371 A104372 A104373

KEYWORD

nonn

AUTHOR

Reinhard Zumkeller, Mar 06 2005

STATUS

approved

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Last modified August 8 01:57 EDT 2020. Contains 336287 sequences. (Running on oeis4.)