A103516 Triangle read by rows: count in a vee.

1, 2, 2, 3, 0, 3, 4, 0, 0, 4, 5, 0, 0, 0, 5, 6, 0, 0, 0, 0, 6, 7, 0, 0, 0, 0, 0, 7, 8, 0, 0, 0, 0, 0, 0, 8, 9, 0, 0, 0, 0, 0, 0, 0, 9, 10, 0, 0, 0, 0, 0, 0, 0, 0, 10, 11, 0, 0, 0, 0, 0, 0, 0, 0, 0, 11, 12, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 12, 13, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 13, 14, 0, 0, 0, 0, 0, 0, 0, 0, 0

Offset

0,2

Comments

Row sums are A103517, antidiagonal sums are A187012.

Links

Table of n, a(n) for n=0..100.

Formula

Number triangle T(n, k)=if(k<=n, 0^(k(n-k))*(n+1), 0)

Example

Triangle begins
1,
2, 2,
3, 0, 3,
4, 0, 0, 4,
5, 0, 0, 0, 5,
6, 0, 0, 0, 0, 6,
7, 0, 0, 0, 0, 0, 7,
8, 0, 0, 0, 0, 0, 0, 8,
...

Mathematica

Join[{1}, Flatten[Table[Flatten[Join[{n, PadRight[{}, n-2, 0], n}]], {n, 2, 15}]]] (* Harvey P. Dale, Mar 23 2013 *)

Prog

(PARI) tabl(nn) = {for (i=1, nn, for (j=1, i, if (j == 1, t = i, if (j==i, t = i, t = 0)); print1(t, ", "); ); print(); ); } \\ Michel Marcus, Aug 30 2013

Crossrefs

Sequence in context: A294898 A297114 A318448 * A233558 A319929 A129234

Adjacent sequences: A103513 A103514 A103515 * A103517 A103518 A103519

Keyword

easy,nonn,tabl

Author

Paul Barry, Feb 09 2005

Status

approved