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A036355 Fibonacci-Pascal triangle read by rows. 12
1, 1, 1, 2, 2, 2, 3, 5, 5, 3, 5, 10, 14, 10, 5, 8, 20, 32, 32, 20, 8, 13, 38, 71, 84, 71, 38, 13, 21, 71, 149, 207, 207, 149, 71, 21, 34, 130, 304, 478, 556, 478, 304, 130, 34, 55, 235, 604, 1060, 1390, 1390, 1060, 604, 235, 55, 89, 420, 1177, 2272, 3310, 3736, 3310 (list; table; graph; refs; listen; history; internal format)
OFFSET

0,4

FORMULA

T(n, m)=T'(n-1, m-1)+T'(n-2, m-2)+T'(n-1, m)+T'(n-2, m), where T'(n, m)=T(n, m) if 0<=m<=n and n >= 0 and T'(n, m)=0 otherwise. Initial term T(0, 0)=1.

T(n,k) is the number of lattice paths from (0,0) to (n,k) using steps (1,0),(2,0),(0,1),(0,2). [Joerg Arndt, Jun 30, 2011]

G.f.: 1/(1-(1+y)*x-(1+y^2)*x^2). - Vladeta Jovovic (vladeta(AT)eunet.rs), Oct 11 2003

EXAMPLE

Triangle begins

1;

1, 1;

2, 2, 2;

3, 5, 5, 3;

5, 10, 14, 10, 5;

8, 20, 32, 32, 20, 8;

13, 38, 71, 84, 71, 38, 13;

21, 71, 149, 207, 207, 149, 71, 21;

34, 130, 304, 478, 556, 478, 304, 130, 34;

55, 235, 604, 1060, 1390, 1390, 1060, 604, 235, 55;

MATHEMATICA

nmax = 11; t[n_, m_] := t[n, m] = tp[n-1, m-1] + tp[n-2, m-2] + tp[n-1, m] + tp[n-2, m]; tp[n_, m_] /; 0 <= m <= n && n >= 0 := t[n, m]; tp[n_, m_] = 0; t[0, 0] = 1; Flatten[ Table[t[n, m], {n, 0, nmax}, {m, 0, n}]] (* From Jean-François Alcover, Nov 09 2011, after formula *)

PROG

(PARI) /* same as in A092566 but use */

steps=[[1, 0], [2, 0], [0, 1], [0, 2]];

/* Joerg Arndt, Jun 30 2011 */

CROSSREFS

Row sums form sequence A002605. T(n, 0) forms the Fibonacci sequence (A000045). T(n, 1) forms sequence A001629.

Derived sequences: A036681, A036682, A036683, A036684, A036692.

Sequence in context: A114639 A071867 A126337 * A095972 A091974 A029073

Adjacent sequences:  A036352 A036353 A036354 * A036356 A036357 A036358

KEYWORD

nonn,tabl,easy,nice

AUTHOR

Floor van Lamoen (fvlamoen(AT)hotmail.com), Dec 28 1998

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Last modified February 17 16:39 EST 2012. Contains 206058 sequences.