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A242342 a(n) = binomial(n, smallest non-divisor of n). 2
0, 0, 3, 4, 10, 15, 21, 56, 36, 120, 55, 792, 78, 364, 105, 560, 136, 3060, 171, 1140, 210, 1540, 253, 42504, 300, 2600, 351, 3276, 406, 27405, 465, 4960, 528, 5984, 595, 376992, 666, 8436, 741, 9880, 820, 111930, 903, 13244, 990, 15180, 1081, 1712304, 1176 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,3

LINKS

Reinhard Zumkeller, Table of n, a(n) for n = 1..10000

FORMULA

a(n) = A007318(n, A007978(n)) for n > 2.

a(2*n-1) = A014105(n).

MATHEMATICA

Join[{0, 0}, Table[Binomial[n, Complement[Range[DivisorSigma[0, n]], Divisors[ n]][[1]]], {n, 3, 50}]] (* Harvey P. Dale, May 23 2019 *)

PROG

(Haskell)

a242342 n = if n <= 2 then 0 else a007318' n (a007978 n)

CROSSREFS

Cf. A014105.

Sequence in context: A285042 A319719 A048155 * A204292 A218277 A103080

Adjacent sequences:  A242339 A242340 A242341 * A242343 A242344 A242345

KEYWORD

nonn

AUTHOR

Reinhard Zumkeller, May 11 2014

STATUS

approved

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Last modified April 22 07:26 EDT 2021. Contains 343163 sequences. (Running on oeis4.)