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Revision History for A066524 (Bold, blue-underlined text is an addition; faded, red-underlined text is a deletion.)

Showing entries 1-10 | older changes
a(n) = n*(2^n - 1).
(history; published version)
#56 by Michel Marcus at Sun Feb 13 04:32:52 EST 2022
STATUS

reviewed

approved

#55 by Joerg Arndt at Sun Feb 13 04:19:17 EST 2022
STATUS

proposed

reviewed

#54 by Joerg Arndt at Sun Feb 13 04:19:04 EST 2022
STATUS

editing

proposed

#53 by Joerg Arndt at Sun Feb 13 04:18:58 EST 2022
MATHEMATICA

Table[n Sum[Binomial[n, j], {j, n}], {n, 0, 30}] (* or *)

PROG

(PARI) { for (n=0, 250, write("b066524.txt", n, " ", n*(2^n - 1)) ) } \\ Harry J. Smith, Feb 21 2010

STATUS

proposed

editing

#52 by Jon E. Schoenfield at Sun Feb 13 03:54:52 EST 2022
STATUS

editing

proposed

#51 by Jon E. Schoenfield at Sun Feb 13 03:54:41 EST 2022
COMMENTS

Form a triangle in which interior members T(i,j) = T(i-1,j-1) + T(i-1,j). The exterior members are given by 1,2,3,...,2*n-1: T(1,1) = n, T(2,1) = n-1, T(3,1) = n-2, ..., T(n,1) = 1 and T(2,2) = n + 1, T(3,3) = n + 2, ..., T(n,n) = 2*n - 1. The sum of all members will reproduce this sequence. For example, with n = 4 the exterior members are 1 to 7: row(1) = 4; row(2) = 3,5; row(3) = 2,8,6; row(4) = 1,10,14,7. The sum of all these members is 60, the fourth term in the sequence. - J. M. Bergot, Oct 16 2012

FORMULA

a(n) = n * sum_Sum_{j = 1..n} Cbinomial(n,j), n >= 0. - Zerinvary Lajos, May 10 2007

PROG

(MAGMAMagma) [n*(2^n-1): n in [0..30]]; // Vincenzo Librandi, Jan 24 2016

STATUS

approved

editing

#50 by Giovanni Resta at Tue Jun 23 06:15:58 EDT 2020
STATUS

reviewed

approved

#49 by Joerg Arndt at Tue Jun 23 05:46:23 EDT 2020
STATUS

proposed

reviewed

#48 by Amiram Eldar at Tue Jun 23 03:17:42 EDT 2020
STATUS

editing

proposed

#47 by Amiram Eldar at Tue Jun 23 02:54:44 EDT 2020
FORMULA

Sum_{n>=1} 1/a(n) = A335764. - Amiram Eldar, Jun 23 2020

CROSSREFS
STATUS

approved

editing