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A186130
Positions of the odd partitions of (2k+1) in reverse lexicographic order converge to this limiting sequence.
4
1, 4, 9, 12, 21, 24, 26, 30, 47, 50, 52, 59, 62, 67, 99, 102, 104, 110, 113, 116, 126, 129, 133, 139, 197, 200, 202, 208, 211, 214, 227, 231, 234, 238, 254, 256, 260, 265, 272, 375, 378, 380, 386, 389, 392, 404, 407, 411, 414, 418, 440, 443, 450, 452, 456, 461, 486, 489, 494, 500, 508, 686, 689, 691
OFFSET
1,2
LINKS
EXAMPLE
The odd partitions of (2*4+1) occur at positions 1, 4, 9, 12, 19, 21, 25, and 30. For (2*5+1) they occur at 1, 4, 9, 12, 20, ..., so for k=5 only four terms have stabilized, giving a(1) = 1, a(2) = 4, a(3) = 9, and a(4) = 12.
MATHEMATICA
<<DiscreteMath`Combinatorica`;
it=Table[Flatten[Position[Partitions[n], q_List/; FreeQ[q, _?EvenQ], 1]], {n, 39, 39+2, 2}]; {{diffat}}=Position[Take[Last[it], Length[First[it] ] ] - First[it] , a_ /; (a!=0), 1, 1]; Take[First[it], diffat -1 ]
CROSSREFS
First differences give A186203.
Sequence in context: A256887 A119640 A332225 * A051233 A124623 A220195
KEYWORD
nonn
AUTHOR
Wouter Meeussen, Feb 13 2011
STATUS
approved