Location via proxy:   [ UP ]  
[Report a bug]   [Manage cookies]                
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.
2
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
1,4
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)
EXAMPLE
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)
MATHEMATICA
Flatten@Array[Table[Table[k, #-k+1], {k, #}]&, 10] (* Giorgos Kalogeropoulos, Jun 08 2021 *)
CROSSREFS
Cf. A004736.
Cf. A000217, A000292, A333516, A345116 (mirror).
Sequence in context: A165620 A128494 A257696 * A198339 A262561 A264990
KEYWORD
base,easy,tabf,nonn
AUTHOR
Amarnath Murthy, Aug 09 2005
EXTENSIONS
Name clarified by Omar E. Pol, Jun 08 2021
STATUS
approved