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URL: https://oeis.org/A324399

⇱ A324399 - OEIS

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A324399
Lexicographically earliest sequence such that a(i) = a(j) => f(i) = f(j) for all i, j >= 1, where f(n) = A000265(n) for all other numbers, except that f(n) = 0 if n is an odd prime, and f(1) = -1 and f(2) = -2.
2
1, 2, 3, 4, 3, 5, 3, 4, 6, 7, 3, 5, 3, 8, 9, 4, 3, 6, 3, 7, 10, 11, 3, 5, 12, 13, 14, 8, 3, 9, 3, 4, 15, 16, 17, 6, 3, 18, 19, 7, 3, 10, 3, 11, 20, 21, 3, 5, 22, 12, 23, 13, 3, 14, 24, 8, 25, 26, 3, 9, 3, 27, 28, 4, 29, 15, 3, 16, 30, 17, 3, 6, 3, 31, 32, 18, 33, 19, 3, 7, 34, 35, 3, 10, 36, 37, 38, 11, 3, 20, 39, 21, 40, 41, 42, 5, 3, 22, 43, 12, 3, 23, 3, 13, 44
OFFSET
1,2
COMMENTS
For all i, j:
A324401(i) = A324401(j) => a(i) = a(j).
LINKS
PROG
(PARI)
up_to = 65537;
rgs_transform(invec) = { my(om = Map(), outvec = vector(length(invec)), u=1); for(i=1, length(invec), if(mapisdefined(om, invec[i]), my(pp = mapget(om, invec[i])); outvec[i] = outvec[pp] , mapput(om, invec[i], i); outvec[i] = u; u++ )); outvec; };
A000265(n) = (n/2^valuation(n, 2));
Aux324399(n) = if(n<3, -n, if(isprime(n), 0, A000265(n)));
v324399 = rgs_transform(vector(up_to, n, Aux324399(n)));
A324399(n) = v324399[n];
CROSSREFS
KEYWORD
nonn
AUTHOR
Antti Karttunen, Mar 01 2019
STATUS
approved