A034972 a(n) = floor(T_(n+1)/T_(n)) where T_n is n-th tangential or "Zag" number (see A000182).

2, 8, 17, 29, 44, 63, 85, 110, 138, 170, 205, 243, 284, 329, 376, 427, 482, 539, 600, 664, 731, 802, 876, 953, 1033, 1116, 1203, 1293, 1386, 1483, 1583, 1685, 1792, 1901, 2014, 2130, 2249, 2371, 2497, 2626, 2758, 2893, 3032, 3174, 3319, 3467, 3619, 3774

Offset

1,1

References

J. Peters and J. Stein, Matematische Tafeln. Revised Russian Edition in 1968, Moscow, Table 9a.

Links

Michael De Vlieger, Table of n, a(n) for n = 1..5000

Formula

a(n) = floor( T(n+1)/T(n) ) where T(n) is n-th coefficient in expansion of tan(x).

Example

a(5) = floor(T(6)/T(5)) = floor(353792/7936) = floor(44.58) = 44.

Mathematica

Map[Floor[#2/#1] & @@ # &, Partition[Table[If[n < 1, 0, ((-16)^n - (-4)^n) Zeta[1 - 2 n]], {n, 49}], 2, 1]] (* Michael De Vlieger, Jul 31 2017, after Michael Somos at A000182 *)

Crossrefs

Cf. A000182.

Sequence in context: A192159 A066564 A357576 * A294537 A294548 A061150

Adjacent sequences: A034969 A034970 A034971 * A034973 A034974 A034975

Keyword

nonn,easy

Author

Labos Elemer

Status

approved