A126576 a(n) = denominator of the sum of reciprocals of the terms in n-th row of triangle A126571.

1, 6, 60, 140, 630, 31416, 34580, 91080, 1093950, 58549260, 6702696, 61910940, 2379795600, 1197892080, 21742542360, 21741799002768, 143830236550, 2559047531040, 38886283310, 333903908520, 24063048428483064

Offset: 1

Author

Leroy Quet, Dec 28 2006

Keywords

• frac
• nonn

Examples

			Row 4 of triangle A126571 is (4,7,5,7).
So a(4) is the denominator of 1/4 +1/7 +1/5 + 1/7 = 103/84.
		

Crossrefs

Cf. A126571, A126575.

Programs

Mathematica

f[m_, n_] := Block[{k = 0, c = n},While[c > 0,k++;While[GCD[k, m] > 1, k++ ];c--;];k];Table[Denominator@Sum[1/f[m, n], {m, n}], {n, 22}] (* Ray Chandler, Dec 29 2006 *)

Extensions

Extended by Ray Chandler, Dec 29 2006