A064139 Sum of divisors of central binomial coefficient binomial(n, floor(n/2)).
1, 3, 4, 12, 18, 42, 48, 144, 312, 728, 1152, 2688, 4704, 10080, 13104, 39312, 54432, 127008, 181440, 423360, 1128960, 2419200, 2903040, 6773760, 14999040, 32140800, 74995200, 160704000, 303264000, 626745600, 646963200, 1940889600
Offset: 1
Keywords
Links
- Harry J. Smith, Table of n, a(n) for n = 1..200
Programs
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Mathematica
a[n_] := DivisorSigma[1, Binomial[n, Floor[n/2]]]; Array[a, 32] (* Amiram Eldar, Apr 01 2024 *)
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PARI
a(n) = sigma(binomial(n, n\2)); \\ Harry J. Smith, Sep 08 2009
Extensions
Offset changed from 0 to 1 by Harry J. Smith, Sep 08 2009