A351091 - OEIS

A351091

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.

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

1,1

LINKS

Table of n, a(n) for n=1..81.

FORMULA

a(n) = A351081(A000265(n)).

PROG

(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); };

A351091(n) = { my(m=1); fordiv(n>>valuation(n, 2), d, m *= A019565(A289813(d))); (m); };