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.

A101461 Row maximum of Catalan triangle with zeros (A053121), i.e., maximum value of (m+1)*binomial(n+1,(n-m)/2)/(n+1) for given n with m same parity as n.

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%I A101461 #19 Sep 17 2019 09:02:37
%S A101461 1,1,1,2,3,5,9,14,28,48,90,165,297,572,1001,2002,3640,7072,13260,
%T A101461 25194,48450,90440,177650,326876,653752,1225785,2414425,4601610,
%U A101461 8947575,17298645,33266625,65132550,124062000,245642760,463991880,927983760
%N A101461 Row maximum of Catalan triangle with zeros (A053121), i.e., maximum value of (m+1)*binomial(n+1,(n-m)/2)/(n+1) for given n with m same parity as n.
%C A101461 There are two maximum values when n is of the form k^2 + 2k - 1 (i.e., 2 less than a square, A008865 offset) in which case m = k +/- 1. In general m is the integer with the same parity as n closest to sqrt(n+2) - 1.
%C A101461 The largest difference between adjacent binomial coefficients on n-th row of Pascal's triangle. - _Vladimir Reshetnikov_, Sep 16 2019
%H A101461 Reinhard Zumkeller, <a href="/A101461/b101461.txt">Table of n, a(n) for n = 0..1000</a>
%F A101461 a(n) = (m+1)*binomial(n+1, (n-m)/2)/(n+1) where m = floor(sqrt(n+2) - (1 + (-1)^floor(n + sqrt(n+2) - 1))/2). a(n) seems to be slightly less than 2^n/n.
%o A101461 (Haskell)
%o A101461 a101461 = maximum . a053121_row  -- _Reinhard Zumkeller_, Mar 04 2012
%K A101461 nonn
%O A101461 0,4
%A A101461 _Henry Bottomley_, Jan 20 2005