A120435 Triangle read by rows: T(n,k) = lcm(1,2,3,4,...,n)/k (1 <= k <= n).

1, 2, 1, 6, 3, 2, 12, 6, 4, 3, 60, 30, 20, 15, 12, 60, 30, 20, 15, 12, 10, 420, 210, 140, 105, 84, 70, 60, 840, 420, 280, 210, 168, 140, 120, 105, 2520, 1260, 840, 630, 504, 420, 360, 315, 280, 2520, 1260, 840, 630, 504, 420, 360, 315, 280, 252, 27720, 13860, 9240

Offset

1,2

Comments

T(n,1) = A003418(n). Row sums yield A025529. - Emeric Deutsch, Jul 24 2006

Links

Table of n, a(n) for n=1..58.

Example

Triangle starts:
   1;
   2,  1;
   6,  3,  2;
  12,  6,  4,  3;
  60, 30, 20, 15, 12;

Maple

T:=proc(n, k) if k<=n then lcm(seq(j, j=1..n))/k else 0 fi end: for n from 1 to 11 do seq(T(n, k), k=1..n) od; # yields sequence in triangular form); # Emeric Deutsch, Jul 24 2006

Crossrefs

Cf. A003418, A094310.

Cf. A003418, A025529.

Sequence in context: A107867 A158442 A252095 * A125901 A094307 A097905

Adjacent sequences: A120432 A120433 A120434 * A120436 A120437 A120438

Keyword

nonn,tabl

Author

Leroy Quet, Jul 15 2006

Extensions

More terms from Emeric Deutsch, Jul 24 2006

Status

approved