A126575 a(n) = numerator of the sum of reciprocals of the terms in n-th row of triangle A126571.

1, 5, 47, 103, 461, 21211, 24183, 62081, 735503, 38230051, 4501873, 40137823, 1571907737, 776878687, 13914337609, 13784887072529, 93498082849, 1626565056793, 25260167753, 213051987097, 15224249929987129

Offset

1,2

Links

Table of n, a(n) for n=1..21.

Example

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

Mathematica

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

Crossrefs

Cf. A126571, A126576.

Sequence in context: A136088 A141890 A056248 * A229613 A335737 A277607

Adjacent sequences: A126572 A126573 A126574 * A126576 A126577 A126578

Keyword

frac,nonn

Author

Leroy Quet, Dec 28 2006

Extensions

Extended by Ray Chandler, Dec 29 2006

Status

approved