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A239258 Number of partitions of 2n having twice as many odd parts as even. 2
1, 0, 1, 2, 5, 8, 15, 23, 39, 59, 94, 140, 216, 316, 472, 682, 994, 1414, 2022, 2837, 3989, 5530, 7663, 10504, 14381, 19509, 26417, 35510, 47618, 63461, 84365, 111553, 147126, 193144, 252892, 329773, 428931, 555852, 718547, 925795, 1189946, 1524863, 1949540 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,4

LINKS

Table of n, a(n) for n=0..42.

EXAMPLE

a(5) counts these 8 partitions of 10:  811, 721, 631, 541, 532, 433, 421111, 322111.

MATHEMATICA

p[n_] := p[n] = Select[IntegerPartitions[2 n], Count[#, _?OddQ] == 2*Count[#, _?EvenQ] &]; t = Table[p[n], {n, 0, 8}] (* shows the partitions *); TableForm[t] (* partitions, vertical format *)

t1 = Table[Length[p[n]], {n, 0, 60}] (* A239258 *)

(* Peter J. C. Moses, Mar 10 2014 *)

CROSSREFS

Cf. A239004.

Sequence in context: A121641 A058884 A073335 * A066897 A078697 A066629

Adjacent sequences:  A239255 A239256 A239257 * A239259 A239260 A239261

KEYWORD

nonn,easy

AUTHOR

Clark Kimberling, Mar 13 2014

EXTENSIONS

More terms from Alois P. Heinz, Mar 15 2014

STATUS

approved

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Last modified May 24 10:48 EDT 2019. Contains 323529 sequences. (Running on oeis4.)