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A117221
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Number of partitions of 3-smooth numbers.
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6
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1, 2, 3, 5, 11, 22, 30, 77, 231, 385, 1575, 3010, 8349, 17977, 147273, 386155, 1741630, 5392783, 18004327, 118114304, 483502844, 4351078600, 22540654445, 129913904637, 1987276856363, 15285151248481, 133978259344888, 365749566870782, 3925922161489422, 49005643635237875
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OFFSET
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1,2
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LINKS
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FORMULA
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MATHEMATICA
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PartitionsP /@ Select[Range[1000], AllTrue[FactorInteger[#][[All, 1]], # <= 3 &] &] (* Jean-François Alcover, Oct 13 2021 *)
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PROG
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(PARI) \\ here is(n) is test for A003586 inclusion.
is(n)={forprime(p=2, 3, n/=p^valuation(n, p)); n==1}
seq(n)={my(A=List(), i=0); while(#A<n, i++; if(is(i), listput(A, numbpart(i)))); Vec(A)} \\ Andrew Howroyd, Jan 02 2020
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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