A294199 Number of partitions of n into powers of 2 such that 1 and 2 cannot both be parts of a particular partition, and 4 and 8 cannot both be parts of a particular partition, and 16 and 32, and so on.
1, 1, 2, 1, 3, 2, 4, 2, 6, 4, 8, 4, 9, 5, 10, 5, 13, 8, 16, 8, 18, 10, 20, 10, 24, 14, 28, 14, 30, 16, 32, 16, 38, 22, 44, 22, 48, 26, 52, 26, 60, 34, 68, 34, 72, 38, 76, 38, 85, 47, 94, 47, 99, 52, 104, 52, 114, 62, 124, 62, 129, 67, 134, 67, 147, 80, 160
Offset: 0
Keywords
Examples
a(10) = 8 where the partitions are the following: 8+2, 8+1+1, 4+4+2, 4+2+2+2, 4+4+1+1, 4+1+1+1+1+1+1, 2+2+2+2+2, 1+1+1+1+1+1+1+1+1+1.
Links
- Vaclav Kotesovec, Table of n, a(n) for n = 0..10000
- Bin Lan and James A. Sellers, Properties of a Restricted Binary Partition Function a la Andrews and Lewis, #A23 INTEGERS 15 (2015), p.2.
Crossrefs
Cf. A070047.
Programs
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Mathematica
nmax = 20; CoefficientList[Series[Product[(1-x^(3*2^(2*k-2)))/(1-x^(2^(k-1))), {k, 1, nmax}], {x, 0, nmax}], x] a[0] = 1; a[1] = 1; a[2] = 2; a[3] = 1; Flatten[{1, 1, 2, 1, Table[If[EvenQ[n], a[n] = a[n-2] + a[Floor[n/4]], a[n] = a[n-1] - a[n-2]], {n, 4, 100}]}]
Formula
G.f.: Product_{k>=1} (1 - x^(2^(2*k-2) + 2^(2*k-1))) / ((1 - x^(2^(2*k-2))) * (1 - x^(2^(2*k-1)))).
G.f.: Product_{k>=1} (1 - x^(3*2^(2*k-2))) / (1 - x^(2^(k-1))).
For n>=1 a(2*n) = a(2*n-2) + a([n/2]).
For n>=1 a(2*n+1) = a(2*n) - a(2*n-1).