The On-Line Encyclopedia of Integer Sequences (OEIS)

Revision History for A025174

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A025174

a(n) = binomial(3n-1, n-1).
(history; published version)

#131 by Peter Luschny at Tue Jul 23 08:23:51 EDT 2024

STATUS

proposed

approved

#130 by Peter Bala at Tue Jul 23 08:21:49 EDT 2024

STATUS

editing

proposed

#129 by Peter Bala at Tue Jul 23 08:21:24 EDT 2024

FORMULA

a(n) = Sum_{k = 0..n-1} binomial(2*n+k-1, k) = Sum_{k = 0..n-1} (-1)^(n+k+1)* binomial(3*n, k). - Peter Bala, Jul 21 2024

STATUS

approved

editing

Discussion

Tue Jul 23

08:21

Peter Bala: Corrected mistake.

#128 by N. J. A. Sloane at Mon Jul 22 15:21:01 EDT 2024

STATUS

proposed

approved

#127 by Peter Bala at Mon Jul 22 11:20:42 EDT 2024

STATUS

editing

proposed

Discussion

Mon Jul 22

12:18

Michel Marcus: your 2nd formula gives 1, -5, 28, -165, 1001, .... ; right ?

#126 by Peter Bala at Sun Jul 21 10:01:23 EDT 2024

FORMULA

a(n) = Sum_{k = 0..n-1} binomial(2*n+k-1, k) = Sum_{k = 0..n-1} (-1)^k* binomial(3*n, k). - Peter Bala, Jul 21 2024

#125 by Peter Bala at Sun Jul 21 08:48:23 EDT 2024

FORMULA

a(n) = Sum_{k = 0..n-1} (-1)^k*binomial(3*n, k). - Peter Bala, Jul 21 2024

STATUS

approved

editing

#124 by Alois P. Heinz at Thu Apr 25 16:23:07 EDT 2024

STATUS

proposed

approved

#123 by Stefano Spezia at Thu Apr 25 16:16:39 EDT 2024

STATUS

editing

proposed

#122 by Stefano Spezia at Thu Apr 25 16:12:45 EDT 2024

CROSSREFS

Cf. A000108, A001045, A005156, A224274.