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A172185 (9,11) Pascal triangle. 1
1, 9, 11, 9, 20, 11, 9, 29, 31, 11, 9, 38, 60, 42, 11, 9, 47, 98, 102, 53, 11, 9, 56, 145, 200, 155, 64, 11, 9, 65, 201, 345, 355, 219, 75, 11, 9, 74, 266, 546, 700, 574, 294, 86, 11, 9, 83, 340, 812, 1246, 1274, 868, 380, 97, 11, 9, 92, 423, 1152, 2058 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

0,2

COMMENTS

Sums of NW-SE diagonals give A022114 (apart from first two terms).

Triangle T(n,k), read by rows, given by (9,-8,0,0,0,0,0,0,0,...) DELTA (11,-10,0,0,0,0,0,0,0,...) where DELTA is the operator defined in A084938. - Philippe Deléham, Oct 09 2011

Row n: Expansion of (9+11x)*(1+x)^(n-1), n > 0. - Philippe Deléham, Oct 09 2011

LINKS

Table of n, a(n) for n=0..59.

FORMULA

T(n,k) = T(n-1,k-1) + T(n-1,k) with T(0,0)=1, T(1,0)=9, T(1,1)=11. - Philippe Deléham, Oct 09 2011

G.f.: (1+8*x+10*y*x)/(1-x-y*x). - Philippe Deléham, Apr 13 2012

EXAMPLE

Triangle begins:

              1

           9,   11

        9,   20,   11

     9,   29,   31,   11

  9,   38,   60,   42,   11

CROSSREFS

Cf. A093644, A172179, A022114.

Sequence in context: A266703 A266701 A172283 * A098728 A233408 A107576

Adjacent sequences:  A172182 A172183 A172184 * A172186 A172187 A172188

KEYWORD

nonn,tabl

AUTHOR

Mark Dols, Jan 28 2010

EXTENSIONS

Corrected and extended by Philippe Deléham, Oct 09 2011

STATUS

approved

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Last modified December 3 15:00 EST 2021. Contains 349463 sequences. (Running on oeis4.)