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A139100
Triangle read by rows: row n lists all partitions of n in the order produced by the shell model of partitions A138151.
6
1, 2, 1, 1, 3, 2, 1, 1, 1, 1, 4, 2, 2, 3, 1, 2, 1, 1, 1, 1, 1, 1, 5, 3, 2, 4, 1, 2, 2, 1, 3, 1, 1, 2, 1, 1, 1, 1, 1, 1, 1, 1, 6, 4, 2, 3, 3, 2, 2, 2, 5, 1, 3, 2, 1, 4, 1, 1, 2, 2, 1, 1, 3, 1, 1, 1, 2, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 7, 5, 2, 4, 3, 3, 2, 2, 6, 1, 4, 2, 1, 3, 3, 1, 2, 2, 2, 1, 5, 1, 1, 3, 2, 1, 1, 4
OFFSET
1,2
COMMENTS
See the integrated diagram of partitions in the entry A138138.
See A138151 for more information.
First 43 members = A026792.
EXAMPLE
Triangle begins:
{(1)}
{(2), (1, 1)}
{(3), (2, 1), (1, 1, 1)}
{(4), (2, 2), (3, 1), (2, 1, 1), (1, 1, 1, 1)}
{(5), (3, 2), (4, 1), (2, 2, 1), (3, 1, 1), (2, 1, 1, 1), (1, 1, 1, 1, 1)}
MATHEMATICA
Table[If[n == 1, ConstantArray[{1}, i - n + 1],
Map[(Join[#, ConstantArray[{1}, i - n]]) &,
Cases[IntegerPartitions[n], x_ /; Last[x] != 1]]], {i, 7}, {n, i, 1, -1}] // Flatten(* Robert Price, May 28 2020 *)
KEYWORD
nonn,tabf,less
AUTHOR
Omar E. Pol, Apr 15 2008
STATUS
approved