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A080382 Triangle read by rows: C[n,Floor[n/2]]/GCD[C[n,Floor[n/2]],C[n,i], i=0,...n; central binomial coefficient is divided by greatest common divisor of binomial coefficients and corresponding central binomial coefficient. 0
1, 1, 1, 2, 1, 2, 3, 1, 1, 3, 6, 3, 1, 3, 6, 10, 2, 1, 1, 2, 10, 20, 10, 4, 1, 4, 10, 20, 35, 5, 5, 1, 1, 5, 5, 35, 70, 35, 5, 5, 1, 5, 5, 35, 70, 126, 14, 7, 3, 1, 1, 3, 7, 14, 126, 252, 126, 28, 21, 6, 1, 6, 21, 28, 126, 252, 462, 42, 42, 14, 7, 1, 1, 7, 14, 42, 42, 462, 924, 77, 14, 21, 28 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

1,4

LINKS

Table of n, a(n) for n=1..83.

EXAMPLE

Triangle begins:

1

1 1

2 1 2

3 1 1 3

6 3 1 3 6

10 2 1 1 2 10

20 10 4 1 4 10 20

35 5 5 1 1 5 5 35

MATHEMATICA

Table[Table[Binomial[n, Floor[n/2]]/GCD[Binomial[n, j], Binomial[n, Floor[n/2]]], {j, 0, n}], {n, 1, 10}]

CROSSREFS

Cf. A007318, A001405, A080381.

Sequence in context: A109004 A103823 A136642 * A106394 A171712 A091412

Adjacent sequences:  A080379 A080380 A080381 * A080383 A080384 A080385

KEYWORD

nonn,tabl

AUTHOR

Labos Elemer, Mar 12 2003

STATUS

approved

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Last modified December 10 09:47 EST 2016. Contains 278999 sequences.