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A206819 Riordan array (1/(1-10*x-10*x^2), x/(1-10*x-10*x^2)). 2
1, 10, 1, 90, 20, 1, 800, 280, 30, 1, 7100, 3400, 570, 40, 1, 63000, 38300, 8800, 960, 50, 1, 559000, 412000, 120600, 18000, 1450, 60, 1, 4960000, 4296000, 1530000, 291000, 32000, 2040, 70, 1 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

0,2

COMMENTS

Row sums are A000042(n+1).

Subtriangle of triangle given by (0, 10, -1, 1, 0, 0, 0, 0, 0, 0, 0, ...) DELTA (1, 0, 0, 0, 0, 0, 0, 0, 0, 0, ...) where DELTA is the operator defined in A084938.

LINKS

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

FORMULA

T(n,k) = 10*T(n-1,k) - 10*T(n-2,k) + T(n-1,k-1).

G.f.: 1/(1-10*x+10*x^2-y*x).

Sum_{k, 0<=k} T(n,k)*x^k = A178869(n+1), A057086(n), A000042(n+1) for x = -1, 0, 1 respectively.

EXAMPLE

Triangle begins :

1

10, 1

90, 20, 1

800, 280, 30, 1

7100, 3400, 570, 40, 1

63000, 38300, 8800, 960, 50, 1

559000, 412000, 120600, 18000, 1450, 60, 1

4960000, 4296000, 1530000, 291000, 32000, 2040, 70, 1

Triangle (0, 10, -1, 1, 0, 0, 0, ...) DELTA (1, 0, 0, 0, 0, 0, 0, 0, ...) begins :

1

0, 1

0, 10, 1

0, 90, 20, 1

0, 800, 280, 30, 1

0, 7100, 3400, 570, 40, 1 ...

CROSSREFS

Cf. A101950, A178865,

Sequence in context: A009227 A305996 A030526 * A178865 A164881 A276379

Adjacent sequences:  A206816 A206817 A206818 * A206820 A206821 A206822

KEYWORD

easy,nonn,tabl

AUTHOR

Philippe Deléham, Feb 12 2012

STATUS

approved

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Last modified March 20 15:43 EDT 2019. Contains 321345 sequences. (Running on oeis4.)