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A351081
a(n) = Product_{d|n} A019565(A289813(d)); a product obtained from the 1-digits present in ternary expansions of the divisors of n.
3
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
OFFSET
1,1
FORMULA
a(n) = A019565(A289813(n)) * A293221(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); };
A351081(n) = { my(m=1); fordiv(n, d, m *= A019565(A289813(d))); (m); };
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Antti Karttunen, Jan 31 2022
STATUS
approved