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A351081
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a(n) = Product_{d|n} A019565(A289813(d)); a product obtained from the 1-digits present in ternary expansions of the divisors of n.
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3
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2, 2, 6, 12, 6, 6, 4, 12, 30, 60, 10, 540, 60, 60, 90, 120, 10, 30, 4, 360, 36, 60, 6, 540, 12, 60, 210, 5040, 14, 18900, 84, 2520, 210, 140, 84, 94500, 140, 140, 18900, 75600, 210, 18900, 140, 12600, 3150, 84, 14, 113400, 168, 2520, 210, 5040, 14, 210, 60, 5040, 36, 84, 6, 1701000, 4, 84, 900, 25200, 900, 18900
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OFFSET
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1,1
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LINKS
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FORMULA
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PROG
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(PARI)
A019565(n) = { my(m=1, p=1); while(n>0, p = nextprime(1+p); if(n%2, m *= p); n >>= 1); (m); };
A289813(n) = { my(d=digits(n, 3)); fromdigits(vector(#d, i, if (d[i]==1, 1, 0)), 2); };
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CROSSREFS
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KEYWORD
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nonn,easy
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AUTHOR
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STATUS
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approved
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