A126339 a(n) = denominator of sum of the reciprocals of all terms in rows 1 through n of table A126336.

1, 1, 2, 2, 3, 12, 66, 462, 42504, 127512, 637560, 8288280, 125580, 2415, 103845, 75599160, 17028710790, 2156970033400, 213540033306600, 26692504163325, 106770016653300, 52103768126810400, 52103768126810400

Offset

1,3

Links

Michael De Vlieger, Table of n, a(n) for n = 1..150

Mathematica

f[l_List] := Append[l, ContinuedFraction[Plus @@ (1/# &) /@ Flatten[l]]]; Denominator@ Table[Plus @@ (1/# &) /@ Flatten@ Nest[f, {{1}}, n - 1], {n, 24}] (* Ray Chandler, Dec 26 2006 *)

Crossrefs

Cf. A126336, A126338.

Sequence in context: A335942 A240133 A293445 * A268725 A153929 A184843

Adjacent sequences: A126336 A126337 A126338 * A126340 A126341 A126342

Keyword

frac,nonn

Author

Leroy Quet, Dec 25 2006

Extensions

Extended by Ray Chandler, Dec 26 2006

Status

approved