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A073888 a(1) = 1, a(2) = 2; a(n+1) = a(n)^n/a(n-1). 3
1, 2, 4, 32, 262144, 38685626227668133590597632 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Table of n, a(n) for n=1..6.

FORMULA

a(n) = 2^A058798(n).

MAPLE

A073888:= proc(n) option remember;

if n<3 then n;

else a(n-1)^(n-1)/a(n-2);

fi; end;

seq(A073888(n), n = 1..7); # G. C. Greubel, May 17 2020

MATHEMATICA

a[n_]:= a[n]= If[n<3, n, a[n-1]^(n-1)/a[n-2]]; Table[a[n], {n, 7}] (* G. C. Greubel, May 17 2020 *)

PROG

(Magma)

I:=[1, 2]; [n le 2 select I[n] else Self(n-1)^(n-1)/Self(n-2): n in [1..7]]; // G. C. Greubel, May 17 2020

(Sage)

def a(n):

    if (n<3): return n

    else: return a(n-1)^(n-1)/a(n-2)

[a(n) for n in (1..7)] # G. C. Greubel, May 17 2020

CROSSREFS

Cf. A058798, A073889.

Sequence in context: A122214 A122216 A100117 * A114642 A200980 A178811

Adjacent sequences:  A073885 A073886 A073887 * A073889 A073890 A073891

KEYWORD

nonn

AUTHOR

Amarnath Murthy, Aug 17 2002

STATUS

approved

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Last modified October 26 22:19 EDT 2021. Contains 348269 sequences. (Running on oeis4.)