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A202941 For n>=0, let n!^(2)=A202367(n+1) and, for 0<=m<=n, C^(2)(n,m)=n!^(2)/(m!^(2)*(n-m)!^(2)). The sequence gives triangle of numbers C^(2)(n,m) with rows of length n+1. 9
1, 1, 1, 1, 10, 1, 1, 21, 21, 1, 1, 20, 42, 20, 1, 1, 11, 22, 22, 11, 1, 1, 2730, 3003, 2860, 3003, 2730, 1, 1, 1, 273, 143, 143, 273, 1, 1 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

0,5

COMMENTS

Conjecture. If p is an odd prime, then the ((p-1)/2))-th row contains two 1's and (p-3)/2 numbers multiple of p.

See also comments in A175669 and A202917.

LINKS

Table of n, a(n) for n=0..35.

FORMULA

If conjectural formula in A202367 is true, then A007814(C^(2)(n,m)) =A007814(C(n,m)).

EXAMPLE

Triangle begins

n/m.|..0.....1.....2.....3.....4.....5.....6.....7

==================================================

.0..|..1

.1..|..1.....1

.2..|..1....10.....1

.3..|..1....21 ...21.....1

.4..|..1....20....42....20.....1

.5..|..1....11....22....22....11.....1

.6..|..1..2730..3003..2860..3003..2730.....1

.7..|..1.....1...273...143...143...273.....1.....1

.8..|

CROSSREFS

Cf. A175669, A053657, A202339, A202367, A202368, A202369, A202917

Sequence in context: A168620 A143683 A146773 * A166341 A113280 A159041

Adjacent sequences:  A202938 A202939 A202940 * A202942 A202943 A202944

KEYWORD

nonn,tabl

AUTHOR

Vladimir Shevelev and Peter J. C. Moses, Dec 26 2011

STATUS

approved

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Last modified May 18 01:37 EDT 2021. Contains 343992 sequences. (Running on oeis4.)