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A034972 a(n) = floor(T_(n+1)/T_(n)) where T_n is n-th tangential or "Zag" number (see A000182). 4
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 (list; graph; refs; listen; history; text; internal format)
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: A224865 A192159 A066564 * A294537 A294548 A061150

Adjacent sequences:  A034969 A034970 A034971 * A034973 A034974 A034975

KEYWORD

nonn,easy

AUTHOR

Labos Elemer

STATUS

approved

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Last modified February 19 19:28 EST 2020. Contains 332047 sequences. (Running on oeis4.)