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A116491
Number of partitions of n into distinct evil numbers.
3
1, 0, 0, 1, 0, 1, 1, 0, 1, 2, 1, 1, 2, 1, 2, 4, 1, 3, 5, 2, 5, 5, 3, 7, 7, 5, 8, 10, 7, 11, 13, 8, 16, 17, 12, 20, 20, 17, 26, 26, 22, 31, 34, 30, 40, 43, 37, 51, 54, 48, 64, 66, 62, 80, 83, 78, 98, 103, 98, 121, 128, 122, 150, 158, 149, 184, 193, 185, 226, 233, 228, 275, 285, 280
OFFSET
0,10
LINKS
N. J. A. Sloane, Transforms
FORMULA
Weigh Transform of characteristic function of A001969.
MAPLE
g:= proc(n) option remember; is(add(i, i=Bits[Split](n))::even) end:
b:= proc(n, i) option remember; `if`(i*(i+1)/2<n, 0, `if`(n=0, 1,
b(n, i-1)+`if`(g(i), b(n-i, min(n-i, i-1)), 0)))
end:
a:= n-> b(n$2):
seq(a(n), n=0..100); # Alois P. Heinz, Sep 08 2019
MATHEMATICA
m = 100;
Product[If[EvenQ[DigitCount[k, 2, 1]], 1 + x^k, 1], {k, 1, m}] + O[x]^m // CoefficientList[#, x]& (* Jean-François Alcover, Sep 11 2019, from PARI *)
PROG
(PARI) seq(n)=Vec(prod(k=1, n, if(hammingweight(k)%2==0, 1+x^k, 1) + O(x*x^n))) \\ Andrew Howroyd, Jun 22 2018
CROSSREFS
Sequence in context: A337511 A261363 A341216 * A131325 A193749 A049824
KEYWORD
nonn
AUTHOR
Christian G. Bower, Feb 17 2006
STATUS
approved