A065422 - OEIS

A065422

If n | a(n) then a(n+1) = a(n)/(highest power of n that divides a(n)), otherwise a(n+1) = n*a(n); a(0) = 1.

1, 1, 2, 6, 24, 120, 20, 140, 1120, 10080, 1008, 11088, 77, 1001, 14014, 210210, 3363360, 57177120, 1029188160, 19554575040, 977728752, 2217072, 100776, 2317848, 96577, 2414425, 62775050, 1694926350, 47457937800, 1376280196200

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OFFSET

0,3

LINKS

Reinhard Zumkeller, Table of n, a(n) for n = 0..1000

Index entries for sequences related to Recamán's sequence

MATHEMATICA

nxt[{n_, a_}]:={n+1, If[Divisible[a, n], a/n^IntegerExponent[a, n], a*n]}; Join[ {1, 1}, Transpose[NestList[nxt, {3, 2}, 30]][[2]]] (* Harvey P. Dale, Jan 08 2013 *)

PROG

(Haskell)

a065422 n = a065422_list !! n

a065422_list = 1 : 1 : f 2 1 where

f n x = x' : f (n+1) x' where

x' | x `mod` n == 0 = until ((> 0) . (`mod` n)) (`div` n) x

| otherwise = x * n

-- Reinhard Zumkeller, Oct 10 2011

CROSSREFS

See A008336 for another version. Cf. A005132.

Sequence in context: A369407 A284567 A360300 * A260850 A008336 A360298

Adjacent sequences: A065419 A065420 A065421 * A065423 A065424 A065425