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A129439 An analogue of Pascal's triangle: T(n,k) = A092143(n)/(A092143(n-k)*A092143(k)), 0 <= k <= n. 2
1, 1, 1, 1, 2, 1, 1, 3, 3, 1, 1, 8, 12, 8, 1, 1, 5, 20, 20, 5, 1, 1, 36, 90, 240, 240, 90, 36, 1, 1, 7, 126, 210, 210, 126, 7, 1, 1, 64, 224, 2688, 1680, 2688, 224, 64, 1, 1, 27, 864, 2016, 9072, 9072, 2016, 864, 27, 1, 1, 100, 1350, 28800, 25200, 181440, 25200, 28800, 1350 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

0,5

COMMENTS

It appears that the T(n,k) are always integers. This would follow from the conjectured prime factorization given in the comments section of A092143.

LINKS

Table of n, a(n) for n=0..64.

FORMULA

T(n,k) = product_{j=1..n} floor(n/j)!/((product_{j=1..n-k} floor((n-k)/j)!)*(product_{j=1..k} floor(k/j)!)).

EXAMPLE

Triangle starts

1

1 1

1 2 1

1 3 3 1

1 8 12 8 1

1 5 20 20 5 1

CROSSREFS

Second column T(n, 1) is A007955, A092143.

Sequence in context: A215292 A124975 A171246 * A176469 A141542 A129453

Adjacent sequences:  A129436 A129437 A129438 * A129440 A129441 A129442

KEYWORD

easy,nonn,tabl

AUTHOR

Peter Bala, Apr 15 2007

STATUS

approved

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Last modified November 28 05:47 EST 2014. Contains 250286 sequences.