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A124959 Triangle read by rows: T(n,k)=a(k)*binom(n,k) (0<=k<=n), where a(0)=1, a(1)=2, a(k)=a(k-1)+3a(k-2) for k>=2 (a(k)=A006138(k)). 0
1, 1, 2, 1, 4, 5, 1, 6, 15, 11, 1, 8, 30, 44, 26, 1, 10, 50, 110, 130, 59, 1, 12, 75, 220, 390, 354, 137, 1, 14, 105, 385, 910, 1239, 959, 314, 1, 16, 140, 616, 1820, 3304, 3836, 2512, 725, 1, 18, 180, 924, 3276, 7434, 11508, 11304, 6525, 1667, 1, 20, 225, 1320, 5460 (list; table; graph; refs; listen; history; internal format)
OFFSET

0,3

COMMENTS

Sum of entries in row n = A006190(n+1).

EXAMPLE

First few rows of the triangle are:

1;

1, 2;

1, 4, 5;

1, 6, 15, 11;

1, 8, 30, 44, 26;

1, 10, 50, 110, 130, 59;

...

MAPLE

a:=proc(n) if n=0 then 1 elif n=1 then 2 else a(n-1)+3*a(n-2) fi end: T:=(n, k)->a(k)*binomial(n, k): for n from 0 to 10 do seq(T(n, k), k=0..n) od; # yields sequence in triangular form

CROSSREFS

Cf. A006138, A006190.

Sequence in context: A038730 A188106 A050166 * A081281 A108198 A121289

Adjacent sequences:  A124956 A124957 A124958 * A124960 A124961 A124962

KEYWORD

nonn,tabl

AUTHOR

Gary W. Adamson (qntmpkt(AT)yahoo.com), Nov 13 2006

EXTENSIONS

Edited by N. J. A. Sloane (njas(AT)research.att.com), Dec 03 2006

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Last modified February 13 17:55 EST 2012. Contains 205525 sequences.