cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A127741 a(n) = (n+1) * A005493(n).

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%I A127741 #27 Jan 03 2025 17:49:22
%S A127741 1,6,30,148,755,4044,22841,136056,853452,5625950,38885297,281170080,
%T A127741 2122313505,16688829122,136457754030,1158155642512,10186602918035,
%U A127741 92711977180164,871936904575985,8462913158427580,84668764368102012,872196382566014506,9241557859113581689
%N A127741 a(n) = (n+1) * A005493(n).
%H A127741 Chai Wah Wu, <a href="/A127741/b127741.txt">Table of n, a(n) for n = 0..250</a>
%F A127741 a(n) = (n+1) * A005493(n).
%e A127741 a(n) = sum of terms in n-th row of A127740. a(2) = 30 = (6 + 9 + 15).
%t A127741 lim=24;A005493=Differences[BellB[Range[lim]]];Array[(#+1)*A005493[[#+1]]&,lim-1,0] (* _James C. McMahon_, Jan 02 2025 *)
%o A127741 (Python)
%o A127741 # requires Python 3.2 or higher. Otherwise use def'n of accumulate in Python docs.
%o A127741 from itertools import accumulate
%o A127741 A127741_list, blist, b = [], [1], 1
%o A127741 for n in range(1,1001):
%o A127741     blist = list(accumulate([b]+blist))
%o A127741     b = blist[-1]
%o A127741     A127741_list.append(blist[-2]*n) # _Chai Wah Wu_, Sep 20 2014
%Y A127741 Cf. A005493, A052889, A011971, A127740 (row sums).
%K A127741 nonn
%O A127741 0,2
%A A127741 _Gary W. Adamson_, Jan 27 2007
%E A127741 Edited by _Jon E. Schoenfield_, May 27 2019