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A388716
Number of integer partitions of n with strictly superdiagonal run-lengths.
7
1, 0, 1, 1, 2, 1, 3, 2, 4, 5, 6, 6, 12, 9, 13, 16, 20, 18, 30, 26, 39, 40, 52, 50, 77, 70, 94, 100, 127, 124, 171, 165, 214, 220, 274, 276, 358, 357, 440, 462, 563, 574, 712, 727, 885, 925, 1096, 1143, 1379, 1428, 1678, 1777, 2085, 2171, 2554, 2674, 3103, 3288
OFFSET
0,5
COMMENTS
A sequence (y_1, ..., y_k) is strictly superdiagonal iff y_i > i for all i = 1..k.
EXAMPLE
The a(2) = 1 through a(10) = 6 partitions:
11 111 22 11111 33 22111 44 333 55
1111 222 1111111 2222 33111 22222
111111 221111 222111 331111
11111111 2211111 2221111
111111111 22111111
1111111111
MATHEMATICA
suppstrQ[mset_]:=And@@Table[mset[[i]]>i, {i, Length[mset]}];
Table[Length[Select[IntegerPartitions[n], suppstrQ[Length/@Split[#]]&]], {n, 0, 10}]
CROSSREFS
For parts instead of run-lengths we have A003106, non-strictly superdiagonal A003114.
The non-strictly superdiagonal version is A388714, reverse A388720.
These partitions are ranked by A388719, non-strictly superdiagonal A388715.
For reversed partitions we have A388721.
A000041 counts integer partitions, strict A000009.
A001522 (complement A064428), A238395 (complement A238394) count partitions w/ diagonal.
A003106 counts strictly superdiagonal partitions, strict A237979, ranks A352830.
A003114 counts superdiagonal partitions, complement A387118, strict partitions A025157.
A114088 counts partitions by excedances.
A115720 and A115994 count partitions by their Durfee square.
A238349 counts compositions by fixed points, complement A352523.
A238352 counts reversed partitions by fixed points.
A352833 counts partitions by fixed points.
A370592 counts choosable partitions (ranks A368100), complement A370593 (ranks A355529).
Sequence in context: A026272 A193564 A022447 * A117194 A340647 A318746
KEYWORD
nonn
AUTHOR
Gus Wiseman, Sep 22 2025
STATUS
approved