A323374 Lexicographically earliest sequence such that for all i, j, a(i) = a(j) => f(i) = f(j) where f(n) = A323373(n) for all other numbers, except f(p) = -(p mod 2) for primes p.

1, 2, 3, 4, 3, 4, 3, 5, 6, 5, 3, 5, 3, 7, 8, 9, 3, 7, 3, 9, 10, 11, 3, 9, 12, 13, 14, 15, 3, 9, 3, 16, 12, 16, 17, 13, 3, 18, 17, 16, 3, 13, 3, 19, 20, 21, 3, 16, 22, 19, 23, 24, 3, 18, 25, 26, 27, 28, 3, 16, 3, 29, 30, 31, 32, 33, 3, 31, 34, 24, 3, 26, 3, 35, 25, 36, 37, 26, 3, 31, 38, 39, 3, 26, 40, 41, 42, 39, 3, 26, 43, 44, 37, 45, 46, 31, 3, 41, 47, 39, 3, 31, 3, 48

Offset

1,2

Comments

For all i, j:

A305801(i) = A305801(j) => a(i) = a(j),

a(i) = a(j) => A039651(i) = A039651(j).

Links

Antti Karttunen, Table of n, a(n) for n = 1..65537

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; };
A049559(n) = gcd(eulerphi(n), n-1);
A160595(n) = if(1==n, n, numerator(eulerphi(n)/(n-1)));
Aux323374(n) = if(isprime(n), -(n%2), [A049559(n), A160595(n)]);
v323374 = rgs_transform(vector(up_to, n, Aux323374(n)));
A323374(n) = v323374[n];

Crossrefs

Cf. A039651, A049559, A160595, A323373.

Cf. also A322587, A322592, A323405.

Sequence in context: A354705 A331730 A304730 * A324197 A259573 A108015

Adjacent sequences: A323371 A323372 A323373 * A323375 A323376 A323377

Keyword

nonn

Author

Antti Karttunen, Jan 13 2019

Status

approved