A131133 a(0)=1; for n > 0, a(n) = (1/n + 1/a(n-1))*lcm(n, a(n-1)).

1, 2, 2, 5, 9, 14, 10, 17, 25, 34, 22, 3, 5, 18, 16, 31, 47, 64, 41, 60, 4, 25, 47, 70, 47, 72, 49, 76, 26, 55, 17, 48, 5, 38, 36, 71, 107, 144, 91, 10, 5, 46, 44, 87, 131, 176, 111, 158, 103, 152, 101, 152, 51, 104, 79, 134, 95, 8, 33, 92, 38, 99, 161, 32, 3, 68, 67, 2, 35, 104

Offset

0,2

Comments

Equivalently, a(0)=1; a(n) = (a(n-1)+n)/gcd(n,a(n-1)). - Ctibor O. Zizka, Feb 15 2008

Links

Harvey P. Dale, Table of n, a(n) for n = 0..1000

Maple

a[0] := 1; for n to 70 do a[n] := (1/n+1/a[n-1])*lcm(n, a[n-1]) end do; seq(a[n], n = 0 .. 70) # Emeric Deutsch, Jun 21 2007

Mathematica

nxt[{n_, a_}]:={n+1, (1/(n+1)+1/a)LCM[n+1, a]}; Transpose[NestList[nxt, {0, 1}, 70]][[2]] (* Harvey P. Dale, Mar 04 2013 *)

Crossrefs

Cf. A131134.

Sequence in context: A278386 A262614 A184296 * A096569 A076607 A325104

Adjacent sequences: A131130 A131131 A131132 * A131134 A131135 A131136

Keyword

nonn

Author

Leroy Quet, Jun 17 2007

Extensions

More terms from Emeric Deutsch, Jun 21 2007

Edited by N. J. A. Sloane, May 16 2008 at the suggestion of R. J. Mathar

Status

approved