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 A257619 Triangle read by rows: T(n,k) = t(n-k, k); t(n,m) = f(m)*t(n-1,m) + f(n)*t(n,m-1), where f(x) = 9*x + 2. 9

%I

%S 1,2,2,4,44,4,8,564,564,8,16,6436,22560,6436,16,32,71404,637844,

%T 637844,71404,32,64,786948,15470232,36994952,15470232,786948,64,128,

%U 8660012,346391196,1660722424,1660722424,346391196,8660012,128

%N Triangle read by rows: T(n,k) = t(n-k, k); t(n,m) = f(m)*t(n-1,m) + f(n)*t(n,m-1), where f(x) = 9*x + 2.

%C Row sums are: 1, 4, 52, 1144, 35464, 1418560, 69509440, 4031547520, 270113683840, 20528639971840, ... (see A144829).

%F T(n,k) = t(n-k, k); t(0,0) = 1, t(n,m) = 0 if n < 0 or m < 0, else t(n,m) = f(m)*t(n-1,m) + f(n)*t(n,m-1), where f(x) = 9*x + 2.

%e 1

%e 2 2

%e 4 44 4

%e 8 564 564 8

%e 16 6436 22560 6436 16

%e 32 71404 637844 637844 71404 32

%e 64 786948 15470232 36994952 15470232 786948 64

%e 128 8660012 346391196 1660722424 1660722424 346391196 8660012 128

%o (PARI) f(x) = 9*x + 2;

%o t(n, m) = if ((n<0) || (m<0), 0, if ((n==0) && (m==0), 1, f(m)*t(n-1,m) + f(n)*t(n,m-1)));

%o tabl(nn) = {for (n=0, nn, for (k=0, n, print1(t(n-k, k), ", "); ); print(); ); } \\ _Michel Marcus_, May 23 2015

%Y Cf. A257608.

%Y Cf. A038208, A256890, A257609, A257610, A257612, A257614, A257616, A257617, A257618.

%Y Similar sequences listed in A256890.

%K nonn,tabl

%O 0,2

%A _Dale Gerdemann_, May 09 2015

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Last modified February 20 07:28 EST 2020. Contains 332067 sequences. (Running on oeis4.)