A093866 a(0)=1, then a(n) is the least number such that there are exactly n numbers coprime to a(n-1) between a(n-1) and a(n) (excluded).

1, 3, 6, 14, 24, 38, 50, 68, 84, 114, 146, 168, 210, 264, 308, 348, 398, 432, 486, 542, 582, 644, 698, 744, 818, 868, 930, 1034, 1098, 1188, 1286, 1348, 1412, 1478, 1546, 1616, 1688, 1762, 1838, 1916, 1996, 2078, 2162, 2254, 2362, 2452, 2544, 2688, 2856

Offset

0,2

Comments

Obviously, from a(3) onwards, all terms are even.

Links

Table of n, a(n) for n=0..48.

Example

a(5) = 24, a(6) = 38, and the five numbers coprime to 24 are 25, 29, 31, 35 and 37.

Mathematica

k = 1; Print[k]; Do[v = 0; m = k + 1; While[v < n, If[GCD[m, k] == 1, v++ ]; m++ ]; k = m; Print[k], {n, 1, 50}] (* Ryan Propper, Jul 25 2005 *)

Crossrefs

Sequence in context: A075189 A291987 A200823 * A056596 A026341 A026271

Adjacent sequences: A093863 A093864 A093865 * A093867 A093868 A093869

Keyword

nonn

Author

Amarnath Murthy, Apr 20 2004

Extensions

More terms from Ryan Propper, Jul 25 2005

Status

approved