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A284171 Number of partitions of n into distinct perfect powers (including 1). 4
1, 1, 0, 0, 1, 1, 0, 0, 1, 2, 1, 0, 1, 2, 1, 0, 1, 2, 1, 0, 1, 2, 1, 0, 1, 3, 2, 1, 2, 3, 2, 1, 2, 3, 3, 2, 4, 5, 3, 2, 4, 5, 3, 2, 4, 6, 4, 2, 4, 7, 5, 2, 5, 8, 5, 2, 5, 8, 6, 3, 5, 10, 8, 4, 6, 10, 8, 4, 6, 10, 9, 5, 7, 11, 10, 6, 8, 12, 10, 6, 8, 13, 11, 7, 9, 15, 13, 7, 10, 16, 14, 8, 10, 16, 15, 9, 10, 17, 16, 9, 11 (list; graph; refs; listen; history; text; internal format)
OFFSET
0,10
COMMENTS
Differs from the sequence A112345 which does not consider 1 as a perfect power.
LINKS
Eric Weisstein's World of Mathematics, Perfect Power
FORMULA
G.f.: Product_{k>=1} (1 + x^A001597(k)).
a(n) = A112345(n-1) + A112345(n).
EXAMPLE
a(25) = 3 because we have [25], [16, 9] and [16, 8, 1].
MATHEMATICA
nmax = 100; CoefficientList[Series[(1 + x) Product[(1 + Boole[GCD @@ FactorInteger[k][[All, 2]] > 1] x^k), {k, 1, nmax}], {x, 0, nmax}], x]
PROG
(PARI) Vec((1 + x) * prod(k=1, 100, 1 + (gcd(factorint(k)[, 2])>1)*x^k) + O(x^101)) \\ Indranil Ghosh, Mar 21 2017
CROSSREFS
Sequence in context: A334540 A334462 A054848 * A286320 A330888 A194525
KEYWORD
nonn
AUTHOR
Ilya Gutkovskiy, Mar 21 2017
STATUS
approved

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Last modified August 29 03:06 EDT 2024. Contains 375510 sequences. (Running on oeis4.)