A027170 - OEIS

A027170

Triangular array T read by rows (4-diamondization of Pascal's triangle). Step 1: t(n,k) = C(n+2,k+1) + C(n+1,k) + C(n+1,k+1) + C(n,k). Step 2: T(n,k) = t(n,k) - t(0,0) + 1. Domain: 0 <= k <= n, n >= 0.

1, 3, 3, 5, 10, 5, 7, 19, 19, 7, 9, 30, 42, 30, 9, 11, 43, 76, 76, 43, 11, 13, 58, 123, 156, 123, 58, 13, 15, 75, 185, 283, 283, 185, 75, 15, 17, 94, 264, 472, 570, 472, 264, 94, 17, 19, 115, 362, 740, 1046, 1046, 740, 362, 115, 19, 21, 138, 481, 1106, 1790, 2096, 1790, 1106, 481, 138, 21

(list; table; graph; refs; listen; history; text; internal format)

OFFSET

0,2

LINKS

Indranil Ghosh, Rows of n = 0..125 of triangle, flattened

EXAMPLE

Triangle starts:

3, 3;

5, 10, 5;

7, 19, 19, 7;

9, 30, 42, 30, 9;

11, 43, 76, 76, 43, 11;

...

MATHEMATICA

t[n_, k_]:= Binomial[n + 2, k + 1] + Binomial[n + 1, k] + Binomial[n + 1, k + 1] + Binomial[n , k]; T[n_, k_] := t[n, k] - t[0, 0] + 1; Flatten[Table[T[n, k], {n, 0, 10}, {k, 0, n}]] (* Indranil Ghosh, Mar 13 2017 *)

PROG

(PARI) alias(C, binomial);

t(n, k) = C(n+2, k+1)+C(n+1, k)+C(n+1, k+1)+C(n, k);

T(n, k) = t(n, k)-t(0, 0)+1;

tabl(nn) = for (n=0, nn, for (k=0, n, print1(T(n, k), ", ")); print());

\\ Michel Marcus, Mar 13 2017

CROSSREFS

Cf. A007318, A026907.

Sequence in context: A146926 A000198 A202674 * A132775 A174102 A217521

Adjacent sequences: A027167 A027168 A027169 * A027171 A027172 A027173

KEYWORD

nonn,tabl

AUTHOR

Clark Kimberling

STATUS

approved