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A342231
Total sum of parts which are powers of 2 in all partitions of n.
1
0, 1, 4, 6, 17, 24, 43, 64, 115, 159, 247, 347, 513, 704, 1001, 1350, 1894, 2513, 3408, 4489, 5989, 7786, 10226, 13172, 17079, 21800, 27938, 35362, 44900, 56402, 70959, 88545, 110617, 137108, 170051, 209599, 258328, 316685, 388072, 473331, 577026, 700524, 849775, 1027167
OFFSET
0,3
FORMULA
G.f.: Sum_{k>=0} 2^k*x^(2^k)/(1 - x^(2^k)) / Product_{j>=1} (1 - x^j).
a(n) = Sum_{k=1..n} A038712(k) * A000041(n-k).
EXAMPLE
For n = 4 we have:
------------------------------------
Partitions Sum of parts
. which are powers of 2
------------------------------------
4 ..................... 4
3 + 1 ................. 1
2 + 2 ................. 4
2 + 1 + 1 ............. 4
1 + 1 + 1 + 1 ......... 4
------------------------------------
Total ................ 17
So a(4) = 17.
MATHEMATICA
nmax = 43; CoefficientList[Series[Sum[2^k x^(2^k)/(1 - x^(2^k)), {k, 0, Floor[Log[2, nmax]] + 1}]/Product[(1 - x^j), {j, 1, nmax}], {x, 0, nmax}], x]
Table[Sum[(2^IntegerExponent[2 k, 2] - 1) PartitionsP[n - k], {k, 1, n}], {n, 0, 43}]
CROSSREFS
KEYWORD
nonn
AUTHOR
Ilya Gutkovskiy, Mar 06 2021
STATUS
approved