A033640 Base 3 digital convolution sequence.

1, 1, 2, 1, 3, 7, 6, 20, 52, 6, 26, 104, 32, 162, 460, 356, 1438, 4048, 712, 3588, 15272, 5012, 27460, 90476, 64944, 300816, 912472, 90476, 155420, 611656, 1067892, 1770024, 4763360, 4151704, 14746316, 39566064, 8915064, 27813084, 109938548, 76294212, 222960908

Offset

0,3

Links

Alois P. Heinz, Table of n, a(n) for n = 0..2000

Example

Suppose base = 3 and a(0)..a(13) are 1 1 2 1 3 7 6 20 52 6 26 104 32 162. In base 3, 14 = 112, so we convolve the last three terms with 1, 1, 2 to obtain 104*1+32*1+162*2 = 460.

Maple

a:= proc(n) option remember; `if`(n=0, 1, (l->
      add(l[i]*a(n-i), i=1..nops(l)))(convert(n, base, 3)))
    end:
seq(a(n), n=0..40);  # Alois P. Heinz, Apr 14 2021

Crossrefs

Cf. A033639, A033641, A033642, A033643, A033644, A033645, A033646, A033647.

Sequence in context: A286616 A019320 A201615 * A112027 A174400 A178079

Adjacent sequences: A033637 A033638 A033639 * A033641 A033642 A033643

Keyword

base,nonn

Author

David W. Wilson

Status

approved