A034971 a(n) = floor(E_(n+1)/E_(n)) where E_n is n-th Euler number (see A028296 and A000364).

5, 12, 22, 36, 53, 73, 97, 124, 154, 187, 223, 263, 306, 352, 402, 454, 510, 569, 632, 697, 766, 838, 914, 992, 1074, 1159, 1248, 1339, 1434, 1532, 1634, 1738, 1846, 1957, 2071, 2189, 2310, 2434, 2561, 2691, 2825, 2962, 3102, 3246, 3393, 3542, 3696, 3852

Offset

1,1

Comments

First nine terms are identical to those of A025740.

References

J. Peters J. and J. Stein, Mathematische Tafeln. Revised Russian Edition in 1968, Moscow, Table 9b.

Links

Table of n, a(n) for n=1..48.

Formula

a(n) = floor(E(n+1)/E(n)) where E(n) is the n-th coefficient in the expansion of sec(x).

Mathematica

Wolfram: ae[ x_ ] := Abs[ EulerE[ 2*x ] ] and fo[ x_ ] := Floor[ N[ ae[ x ]/ae[ x-1 ], 80 ] ]
Table[Floor[Abs[EulerE[2n+2]]/Abs[EulerE[2n]]], {n, 60}] (* Harvey P. Dale, May 01 2011 *)

Crossrefs

Cf. A028296, A000364, A025740.

Sequence in context: A025734 A153818 A069627 * A025740 A225247 A299257

Adjacent sequences: A034968 A034969 A034970 * A034972 A034973 A034974

Keyword

nonn,easy

Author

Labos Elemer

Status

approved