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Numerators of inverse unimodal analog of binomial coefficients: binomial(n,m) = Sum_{k=0..n-m} a(2*k+m-1, 2*k).
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%I #11 Aug 27 2019 02:57:07

%S 1,1,1,1,3,1,1,15,2,1,1,35,3,5,1,1,315,4,35,3,1,1,693,5,105,6,7,1,1,

%T 3003,6,1155,10,63,4,1,1,6435,7,3003,15,231,10,9,1,1,109395,8,15015,

%U 21,3003,20,99,5,1,1,230945,9,36465,28,9009,35,429,15,11,1

%N Numerators of inverse unimodal analog of binomial coefficients: binomial(n,m) = Sum_{k=0..n-m} a(2*k+m-1, 2*k).

%H G. C. Greubel, <a href="/A072285/b072285.txt">Rows n = 0..100 of triangle, flattened</a>

%F a(n, m) = binomial(n-m/2+1, n-m+1) - binomial(n-m/2, n-m+1).

%t a[n_, m_]:= Binomial[n -m/2 +1, n-m+1] - Binomial[n -m/2, n-m+1]; Flatten[Table[Numerator[a[n, m]], {n, 0, 11}, {m, 0, n}]]

%o (PARI) a(n,m) = binomial(n-m/2, n-m);

%o for(n=0,10, for(m=0,n, print1(numerator(a(n,m)), ", "))) \\ _G. C. Greubel_, Aug 26 2019

%o (Sage) [[numerator( binomial(n-m/2, n-m) ) for m in (0..n)] for n in (0..11)] # _G. C. Greubel_, Aug 26 2019

%Y Cf. A072286, A071922.

%K nonn,easy,frac,tabl

%O 0,5

%A Michele Dondi (bik.mido(AT)tiscalinet.it), Jul 11 2002