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A351091
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a(n) = Product_{d|A000265(n)} A019565(A289813(d)); a product obtained from the 1-digits present in ternary expansions of the odd divisors of n.
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5
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2, 2, 6, 2, 6, 6, 4, 2, 30, 6, 10, 6, 60, 4, 90, 2, 10, 30, 4, 6, 36, 10, 6, 6, 12, 60, 210, 4, 14, 90, 84, 2, 210, 10, 84, 30, 140, 4, 18900, 6, 210, 36, 140, 10, 3150, 6, 14, 6, 168, 12, 210, 60, 14, 210, 60, 4, 36, 14, 6, 90, 4, 84, 900, 2, 900, 210, 60, 10, 90, 84, 10, 30, 4, 140, 540, 4, 60, 18900, 4, 6, 2310
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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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