OFFSET
0,2
LINKS
John Cerkan, Table of n, a(n) for n = 0..482
Peter Luschny, An old operation on sequences: the Seidel transform.
J. Millar, N. J. A. Sloane and N. E. Young, A new operation on sequences: the Boustrophedon transform, J. Combin. Theory, 17A (1996) 44-54 (Abstract, pdf, ps).
N. J. A. Sloane, Transforms.
Wikipedia, Boustrophedon transform.
EXAMPLE
The array begins:
1
1 -> 2
4 <- 3 <- 1
2 -> 6 -> 9 -> 10
30 <- 28 <- 22 <- 13 <- 3
- John Cerkan, Jan 26 2017
MATHEMATICA
t[n_, 0] := If[n == 0, 1, PartitionsP[n-1]]; t[n_, k_] := t[n, k] = t[n, k - 1] + t[n-1, n-k]; a[n_] := t[n, n]; Array[a, 30, 0] (* Jean-François Alcover, Feb 12 2016 *)
PROG
(Haskell)
a000733 n = sum $ zipWith (*) (a109449_row n) (1 : a000041_list)
-- Reinhard Zumkeller, Nov 04 2013
(Python)
from itertools import count, accumulate, islice
from sympy import npartitions
def A000733_gen(): # generator of terms
yield 1
blist = (1, )
for i in count(0):
yield (blist := tuple(accumulate(reversed(blist), initial=npartitions(i))))[-1]
CROSSREFS
KEYWORD
nonn
AUTHOR
STATUS
approved