A292791 The numerator of the real part of E(2n-1, i), where E(n, x) is the Euler polynomial.

-1, 7, -11, 199, -361, 8017, -63311, 10775663, -37120861, 2572609327, -54738555011, 11225458402189, -170606509547761, 24269619087650437, -998364772178081111, 1505193846304099711711, -10065529459831250937061, 2427246234079407797537347, -163790353311268893725697611

Offset

1,2

Comments

The imaginary part is +-i.

The denominators are powers of two; A171977(n) = 2^A001511(n).

For E(2n, i) see A292792.

a(4n) == +-1 (mod 6),

a(4n+1) == 5 (mod 6),

a(4n+2) == 1 (mod 6),

a(4n+3) == 1 (mod 6).

Inspired by A291897.

Links

Robert G. Wilson v, Table of n, a(n) for n = 1..276

Example

a(3) = -11 since E(5, i) = -11/2 + i.

Mathematica

f[n_] := Numerator[ EulerE[2n -1, I] - I^(2n -1)]; Array[f, 19]

Crossrefs

Cf. A292792.

Sequence in context: A154303 A128340 A106716 * A106818 A231329 A322950

Adjacent sequences: A292788 A292789 A292790 * A292792 A292793 A292794

Keyword

sign

Author

Robert G. Wilson v, Sep 23 2017

Status

approved