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A205549 Symmetric matrix by antidiagonals: C(max(i+2,j+2),min(i+2,j+2)), i>=1, j>=1. 0
1, 4, 4, 10, 1, 10, 20, 5, 5, 20, 35, 15, 1, 15, 35, 56, 35, 6, 6, 35, 56, 84, 70, 21, 1, 21, 70, 84, 120, 126, 56, 7, 7, 56, 126, 120, 165, 210, 126, 28, 1, 28, 126, 210, 165, 220, 330, 252, 84, 8, 8, 84, 252, 330, 220, 286, 495, 462, 210, 36, 1, 36, 210, 462 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Table of n, a(n) for n=1..64.

EXAMPLE

Northwest corner:

1....4....10...20...35

4....1....5....15...35

10...5....1....6....21

20...15...6....1....7

MATHEMATICA

g[k_] := k + 2;

f[i_, j_] := Binomial[Max[g[i], g[j]], Min[g[i], g[j]]]

TableForm[Table[f[i, j], {i, 1, 10}, {j, 1, 10}]]

Flatten[Table[f[i, n + 1 - i], {n, 1, 14}, {i, 1, n}]]

CROSSREFS

Cf. A205456, A205548.

Sequence in context: A202409 A091016 A198025 * A120395 A321078 A160723

Adjacent sequences:  A205546 A205547 A205548 * A205550 A205551 A205552

KEYWORD

nonn,tabl

AUTHOR

Clark Kimberling, Jan 28 2012

STATUS

approved

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Last modified October 17 13:32 EDT 2021. Contains 348049 sequences. (Running on oeis4.)