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A131133
a(0)=1; for n > 0, a(n) = (1/n + 1/a(n-1))*lcm(n, a(n-1)).
2
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
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
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