A110730 Irregular triangle read by rows in which row n lists n 1's followed by (n-1) 2's followed by (n-3) 3's ... followed by 1 n.

1, 1, 1, 2, 1, 1, 1, 2, 2, 3, 1, 1, 1, 1, 2, 2, 2, 3, 3, 4, 1, 1, 1, 1, 1, 2, 2, 2, 2, 3, 3, 3, 4, 4, 5, 1, 1, 1, 1, 1, 1, 2, 2, 2, 2, 2, 3, 3, 3, 3, 4, 4, 4, 5, 5, 6, 1, 1, 1, 1, 1, 1, 1, 2, 2, 2, 2, 2, 2, 3, 3, 3, 3, 3, 4, 4, 4, 4, 5, 5, 5, 6, 6, 7, 1, 1, 1, 1, 1, 1, 1, 1, 2, 2, 2, 2, 2, 2, 2, 3, 3, 3, 3, 3, 3

Offset: 1

Author

Amarnath Murthy, Aug 09 2005

Keywords

• base
• easy
• tabf
• nonn

Comments

From Omar E. Pol, May 08 2021: (Start)

Row n has length A000217(n).

Row sums give A000292, n >= 1.

Row n lists the terms of the n-th row A333516 in nondecreasing order.

(End)

Examples

			From _Omar E. Pol_, May 08 2021: (Start)
Triangle begins:
  1;
  1, 1, 2;
  1, 1, 1, 2, 2, 3;
  1, 1, 1, 1, 2, 2, 2, 3, 3, 4;
  1, 1, 1, 1, 1, 2, 2, 2, 2, 3, 3, 3, 4, 4, 5;
  1, 1, 1, 1, 1, 1, 2, 2, 2, 2, 2, 3, 3, 3, 3, 4, 4, 4, 5, 5, 6;
  ...
(End)
		

Crossrefs

Cf. A004736.

Cf. A000217, A000292, A333516, A345116 (mirror).

Programs

Mathematica

Flatten@Array[Table[Table[k,#-k+1],{k,#}]&,10] (* Giorgos Kalogeropoulos, Jun 08 2021 *)

Extensions

Name clarified by Omar E. Pol, Jun 08 2021