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URL: https://oeis.org/A325382

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A325382
Lexicographically earliest sequence such that for all i, j, a(i) = a(j) => f(i) = f(j) where f(n) = [A048250(n), A126795(n)] for all other numbers, except f(p) = -(p mod 2) for primes.
3
1, 2, 3, 4, 3, 5, 3, 4, 6, 7, 3, 8, 3, 9, 10, 4, 3, 5, 3, 7, 11, 12, 3, 8, 13, 14, 6, 15, 3, 16, 3, 4, 17, 18, 19, 8, 3, 20, 21, 7, 3, 22, 3, 23, 10, 24, 3, 8, 25, 7, 26, 14, 3, 5, 27, 28, 29, 30, 3, 31, 3, 32, 11, 4, 33, 34, 3, 18, 35, 36, 3, 8, 3, 37, 10, 38, 39, 40, 3, 7, 6, 41, 3, 42, 43, 44, 45, 23, 3, 46, 47, 48, 49, 36, 50, 8, 3, 9, 17, 7, 3, 51, 3, 14
OFFSET
1,2
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; };
A048250(n) = factorback(apply(p -> p+1, factor(n)[, 1]));
A126795(n) = gcd(n, A048250(n));
Aux325382(n) = if(isprime(n), -(n%2), [A048250(n), A126795(n)]);
v325382 = rgs_transform(vector(up_to, n, Aux325382(n)));
A325382(n) = v325382[n];
CROSSREFS
KEYWORD
nonn
AUTHOR
Antti Karttunen, May 08 2019
STATUS
approved