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)}].

1, 2, 16, 8388608, 1532495540865888858358347027150309183618739122183602176

Offset: 1

Author

Amarnath Murthy, May 22 2004

Keywords

• nonn

Comments

The next term has 535 digits. - Harvey P. Dale, Jan 31 2020

Examples

			a(5) = 8388608^8/16 = 1.53249554e+54.
a(6) =~ 8.5173068734e+534.
		

Crossrefs

Cf. A093985, A093986.

Programs

Mathematica

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 *)
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 *)

Extensions

Edited and extended by Robert G. Wilson v, May 24 2004