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A093987 a(1) = 1, a(2) = 2, a(n+1) = a(n)^(2n)/ a(n-1). Symmetrically a(n) = {a(n-1)*a(n+1)}^[1/{(n-1) +(n+1)}]. 0

%I #8 Jan 31 2020 19:40:46

%S 1,2,16,8388608,

%T 1532495540865888858358347027150309183618739122183602176

%N a(1) = 1, a(2) = 2, a(n+1) = a(n)^(2n)/ a(n-1). Symmetrically a(n) = {a(n-1)*a(n+1)}^[1/{(n-1) +(n+1)}].

%C The next term has 535 digits. - _Harvey P. Dale_, Jan 31 2020

%e a(5) = 8388608^8/16 = 1.53249554e+54.

%e a(6) =~ 8.5173068734e+534.

%t a[1] = 1; a[2] = 2; a[n_] := a[n - 1]^(2n - 2)/a[n - 2]; Table[ a[n], {n, 6}] (* _Robert G. Wilson v_, May 24 2004 *)

%t RecurrenceTable[{a[1]==1,a[2]==2,a[n+1]==a[n]^(2n)/a[n-1]},a,{n,5}] (* _Harvey P. Dale_, Jan 31 2020 *)

%Y Cf. A093985, A093986.

%K nonn

%O 1,2

%A _Amarnath Murthy_, May 22 2004

%E Edited and extended by _Robert G. Wilson v_, May 24 2004

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Last modified March 29 01:36 EDT 2024. Contains 371264 sequences. (Running on oeis4.)