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A300834
a(n) = Product_{d|n, d<n} A019565(A003714(d)), where A003714(n) is the n-th Fibbinary number.
7
1, 2, 2, 6, 2, 30, 2, 60, 10, 42, 2, 4200, 2, 126, 70, 660, 2, 9240, 2, 13860, 210, 330, 2, 5082000, 14, 78, 220, 32760, 2, 3783780, 2, 42900, 550, 780, 294, 924924000, 2, 1092, 130, 41621580, 2, 3898440, 2, 112200, 60060, 306, 2, 28078050000, 42, 235620, 1300, 92820, 2, 200119920, 770, 128648520, 1820, 1122, 2, 424964656116000, 2, 3366
OFFSET
1,2
LINKS
FORMULA
a(n) = Product_{d|n, d<n} A019565(A003714(d)).
For n >= 1, A001222(a(n)) = A300836(n).
PROG
(PARI)
A072649(n) = { my(m); if(n<1, 0, m=0; until(fibonacci(m)>n, m++); m-2); }; \\ From A072649
A003714(n) = { my(s=0, w); while(n>2, w = A072649(n); s += 2^(w-1); n -= fibonacci(w+1)); (s+n); }
A019565(n) = {my(j, v); factorback(Mat(vector(if(n, #n=vecextract(binary(n), "-1..1")), j, [prime(j), n[j]])~))}; \\ From A019565
A300834(n) = { my(m=1); fordiv(n, d, if(d < n, m *= A019565(A003714(d)))); m; };
CROSSREFS
Cf. A003714, A019565, A300835 (rgs-transform of this sequence), A300836.
Sequence in context: A306387 A308692 A319352 * A293214 A293216 A319708
KEYWORD
nonn
AUTHOR
Antti Karttunen, Mar 18 2018
STATUS
approved