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A332309 Number of compositions (ordered partitions) of n into distinct parts where no part is a multiple of 3. 3
1, 1, 1, 2, 1, 3, 4, 9, 9, 6, 15, 17, 38, 29, 53, 70, 65, 91, 150, 229, 277, 236, 439, 489, 514, 897, 993, 1632, 1521, 2339, 2972, 3257, 4121, 5992, 5303, 7729, 10932, 15157, 17653, 18398, 26305, 31683, 34408, 51885, 58173, 61098, 90519, 101249, 143402, 156905 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,4

LINKS

Alois P. Heinz, Table of n, a(n) for n = 0..5000

Index entries for sequences related to compositions

EXAMPLE

a(9) = 6 because we have [8, 1], [7, 2], [5, 4], [4, 5], [2, 7] and [1, 8].

MAPLE

b:= proc(n, i, p) option remember; `if`(i*(i+1)/2<n, 0, `if`(n=0,

      p!, add(b(n-i*j, i-1, p+j), j=0..min(irem(i, 3), 1, n/i))))

    end:

a:= n-> b(n$2, 0):

seq(a(n), n=0..55);  # Alois P. Heinz, Feb 09 2020

CROSSREFS

Cf. A000726, A003105, A032020, A032021, A332310, A332311.

Sequence in context: A134876 A019612 A007444 * A166476 A052950 A086851

Adjacent sequences:  A332306 A332307 A332308 * A332310 A332311 A332312

KEYWORD

nonn

AUTHOR

Ilya Gutkovskiy, Feb 09 2020

STATUS

approved

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Last modified June 6 03:56 EDT 2020. Contains 334858 sequences. (Running on oeis4.)