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A126575
a(n) = numerator of the sum of reciprocals of the terms in n-th row of triangle A126571.
1
1, 5, 47, 103, 461, 21211, 24183, 62081, 735503, 38230051, 4501873, 40137823, 1571907737, 776878687, 13914337609, 13784887072529, 93498082849, 1626565056793, 25260167753, 213051987097, 15224249929987129
OFFSET
1,2
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
Sequence in context: A136088 A141890 A056248 * A229613 A335737 A277607
KEYWORD
frac,nonn
AUTHOR
Leroy Quet, Dec 28 2006
EXTENSIONS
Extended by Ray Chandler, Dec 29 2006
STATUS
approved