A237587 Triangle read by rows in which row n lists the first n odd squares in decreasing order.

1, 9, 1, 25, 9, 1, 49, 25, 9, 1, 81, 49, 25, 9, 1, 121, 81, 49, 25, 9, 1, 169, 121, 81, 49, 25, 9, 1, 225, 169, 121, 81, 49, 25, 9, 1, 289, 225, 169, 121, 81, 49, 25, 9, 1, 361, 289, 225, 169, 121, 81, 49, 25, 9, 1, 441, 361, 289, 225, 169, 121, 81, 49, 25, 9, 1

Offset: 1

Author

Omar E. Pol, Feb 16 2014

Keywords

• nonn
• tabl

Comments

The sum of row n gives A000447(n).

The alternatig sum of row n gives A077221(n).

Examples

			Triangle begins:
1;
9,     1;
25,    9,   1;
49,   25,   9,   1;
81,   49,  25,   9,   1;
121,  81,  49,  25,   9,   1;
169, 121,  81,  49,  25,   9,   1;
225, 169, 121,  81,  49,  25,   9,   1;
289, 225, 169, 121,  81,  49,  25,   9,   1;
361, 289, 225, 169, 121,  81,  49,  25,   9,   1;
...
		

Crossrefs

Cf. A000290, A000447, A016754, A055461, A077221.

Formula

T(n,k) = (2*(n-k+1)-1)^2, n >=1, 1<=k<=n.