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A305215
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a(n) is the number of numbers whose largest prime power factor equals A000961(n).
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3
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1, 1, 2, 2, 6, 12, 8, 16, 48, 96, 48, 240, 480, 960, 960, 960, 3840, 7680, 3072, 18432, 36864, 73728, 147456, 147456, 442368, 884736, 1769472, 589824, 4128768, 8257536, 16515072, 33030144, 16515072, 82575360, 165150720, 330301440, 660602880, 1321205760
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OFFSET
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1,3
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COMMENTS
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The largest prime power factor of a number n is given by A034699(n).
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LINKS
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FORMULA
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EXAMPLE
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-- ---- ---------- ----
1 1 1 { 1 }
2 1 2 { 2 }
3 2 3 { 3, 6 }
4 2 4 { 4, 12 }
5 6 5 { 5, 10, 15, 20, 30, 60 }
6 12 7 { 7, 14, 21, 28, 35, 42, 70, 84, 105, 140, 210, 420 }
7 8 8 { 8, 24, 40, 56, 120, 168, 280, 840 }
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PROG
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(PARI) my(l=1); for (k=1, 103, if (omega(k) <= 1, l = lcm(l, k); print1 (numdiv(l/k) ", ")))
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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