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Revision History for A122045

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Showing entries 1-10 | older changes

A122045

Euler (or secant) numbers E(n).
(history; published version)

#192 by Peter Luschny at Sat Jun 01 05:22:01 EDT 2024

STATUS

reviewed

approved

#191 by Vaclav Kotesovec at Sat Jun 01 05:05:38 EDT 2024

STATUS

proposed

reviewed

#190 by Vaclav Kotesovec at Sat Jun 01 05:05:17 EDT 2024

STATUS

editing

proposed

#189 by Vaclav Kotesovec at Sat Jun 01 05:03:13 EDT 2024

MATHEMATICA

a[0] := 1; a[n_?OddQ] := 0; a[n_?EvenQ] := a[n] = -Sum[a[n - k]/k!, {k, 2, n, 2}]; Map[#! a[#] &, Range[0, 30]] (* Oliver Seipel, May 20 2024 *)

Discussion
Sat Jun 01	05:05	Vaclav Kotesovec: Of your two programs, I kept the one with Binomial, which is faster. But in the case of this sequence, EulerE is the fastest.

#188 by Vaclav Kotesovec at Sat Jun 01 04:54:46 EDT 2024

MATHEMATICA

a[0] := 1; a[n_?OddQ] := 0; a[n_?EvenQ] := a[n] = -Sum[a[k] Binomial[n, k], {k, 0, n - 1, 2}]; Map[a, Range[0; , 30]] (* _Oliver Seipel_, May 20 2024 *)

a[0] := 1; a[n_?OddQ] := 0; a[n_?EvenQ] :=] := a[n] = -Sum[a[n - k]/k!, {k, 2, n, 2}]; Map[#! a[#] &, Range[0, 30]] (* _Oliver Seipel_, May 20 2024 *)

a[n] = -Sum[a[k] Binomial[n, k], {k, 0, n - 1, 2}]; Map[a,

Range[0, 30]] (* Oliver Seipel, May 20 2024 *)

a[0] := 1; a[n_?OddQ] := 0;

a[n_?EvenQ] := a[n] = -Sum[a[n - k]/k!, {k, 2, n, 2}]; Map[#! a[#] &,

Range[0, 30]] (* Oliver Seipel, May 20 2024 *)

STATUS

proposed

editing

#187 by Oliver Seipel at Mon May 20 08:02:25 EDT 2024

STATUS

editing

proposed

Discussion
Mon May 20	08:42	Michel Marcus: why 4 lines ?

#186 by Oliver Seipel at Mon May 20 07:53:23 EDT 2024

MATHEMATICA

a[0] := 1; a[n_?OddQ] := 0;

a[n_?EvenQ] :=

a[n] = -Sum[a[k] Binomial[n, k], {k, 0, n - 1, 2}]; Map[a,

Range[0, 30]] (* Oliver Seipel, May 20 2024 *)

a[0] := 1; a[n_?OddQ] := 0;

a[n_?EvenQ] := a[n] = -Sum[a[n - k]/k!, {k, 2, n, 2}]; Map[#! a[#] &,

Range[0, 30]] (* Oliver Seipel, May 20 2024 *)

STATUS

approved

editing

#185 by Andrew Howroyd at Sat Oct 28 11:41:59 EDT 2023

STATUS

reviewed

approved

#184 by Joerg Arndt at Sat Oct 28 11:34:25 EDT 2023

STATUS

proposed

reviewed

#183 by Michel Marcus at Sat Oct 28 10:28:23 EDT 2023

STATUS

editing

proposed

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Last modified August 18 02:03 EDT 2024. Contains 375255 sequences. (Running on oeis4.)