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A020740 Max_{k=0..n} d(C(n,k)) - d(C(n,[ n/2 ])), where d() = number of divisors. 2
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 12, 16, 32, 0, 0, 0, 64, 48, 0, 0, 96, 0, 0, 0, 192, 256, 0, 256, 384, 0, 0, 0, 0, 0, 832, 768, 512, 0, 0, 0, 0, 384, 576, 1536, 3072, 2048, 8448, 7680, 5632, 0, 0, 0, 14336, 3584, 0, 0, 3072 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,18

LINKS

Table of n, a(n) for n=1..64.

EXAMPLE

n=20, d(C[ 20,10 ])= 48 and the d(C[ 20,k ]) values are 1,6,8,16,24,40,64,80. The maximum is 80, so the difference is 80-48 = 32.

MATHEMATICA

Table[Max[Table[DivisorSigma[0, Binomial[n, k]], {k, 0, n}]] - DivisorSigma[ 0, Binomial[n, Floor[n/2]]], {n, 70}] (* Harvey P. Dale, Jul 18 2013 *)

CROSSREFS

Cf. A000005, A048485, A048569.

Sequence in context: A192609 A157678 A109240 * A086980 A256934 A058203

Adjacent sequences:  A020737 A020738 A020739 * A020741 A020742 A020743

KEYWORD

nonn

AUTHOR

Labos Elemer

STATUS

approved

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Last modified January 27 18:35 EST 2020. Contains 331296 sequences. (Running on oeis4.)