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A365463
a(n) = gcd(n, A356867(n)), where A356867 is Sycamore's Doudna variant D(3).
6
1, 2, 3, 1, 1, 6, 1, 8, 9, 1, 1, 3, 1, 2, 3, 2, 1, 18, 1, 4, 3, 1, 1, 24, 25, 2, 27, 1, 1, 3, 1, 4, 3, 2, 7, 9, 1, 2, 3, 5, 1, 6, 1, 4, 9, 1, 1, 6, 1, 50, 3, 4, 1, 54, 11, 2, 3, 1, 1, 12, 1, 2, 9, 1, 5, 3, 1, 4, 3, 10, 1, 72, 1, 2, 75, 1, 1, 6, 1, 16, 81, 1, 1, 3, 5, 2, 3, 2, 1, 9, 91, 2, 3, 1, 5, 12, 1, 2, 9, 5, 1, 6, 1, 8, 21
OFFSET
1,2
LINKS
FORMULA
a(n) = gcd(n, A365462(n)) = gcd(A356867(n), A365462(n)).
a(n) = n / A365464(n) = A356867(n) / A365465(n).
For all n >= 1, A007949(a(n)) = A007949(n), A011655(a(n)) = A011655(n).
PROG
(PARI)
up_to = 19683;
A356867list(up_to) = { my(v=vector(up_to), met=Map(), h=0, ak); for(i=1, #v, if(1==vecsum(digits(i, 3)), v[i] = i; h = i, ak = v[i-h]; forprime(p=2, , if(3!=p && !mapisdefined(met, p*ak), v[i] = p*ak; break))); mapput(met, v[i], i)); (v); };
v356867 = A356867list(up_to);
A356867(n) = v356867[n];
A365463(n) = gcd(n, A356867(n));
CROSSREFS
Cf. A007949, A356867, A364957 (Dirichlet inverse), A365462, A365464, A365465.
Cf. also A364500.
Sequence in context: A140878 A182933 A342673 * A068348 A308290 A204167
KEYWORD
nonn
AUTHOR
Antti Karttunen, Sep 15 2023
STATUS
approved