A323888 Lexicographically earliest sequence such that for all i, j, a(i) = a(j) => f(i) = f(j) where f(n) = [A032742(n),A302042(n)] for all n > 1, with f(1) = 0.

1, 2, 2, 3, 2, 4, 2, 5, 4, 6, 2, 7, 2, 8, 6, 9, 2, 10, 2, 11, 12, 13, 2, 14, 6, 15, 16, 17, 2, 18, 2, 19, 20, 21, 8, 22, 2, 23, 24, 25, 2, 26, 2, 27, 28, 29, 2, 30, 8, 31, 32, 33, 2, 34, 35, 36, 37, 38, 2, 39, 2, 40, 41, 42, 24, 43, 2, 44, 45, 46, 2, 47, 2, 48, 49, 50, 13, 51, 2, 52, 53, 54, 2, 55, 56, 57, 58, 59, 2, 60, 61, 62, 63, 64, 65, 66, 2, 67, 68, 69, 2, 70, 2

Offset: 1

Author

Antti Karttunen, Feb 08 2019

Keywords

• nonn

Comments

For all i, j:

A305800(i) = A305800(j) => a(i) = a(j),

a(i) = a(j) => A001222(i) = A001222(j),

a(i) = a(j) => A253557(i) = A253557(j).

Links

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

Crossrefs

Cf. A032742, A302042.

Cf. also A001222, A253557, A300247, A305800.

Programs

PARI

up_to = 65537;
ordinal_transform(invec) = { my(om = Map(), outvec = vector(length(invec)), pt); for(i=1, length(invec), if(mapisdefined(om,invec[i]), pt = mapget(om, invec[i]), pt = 0); outvec[i] = (1+pt); mapput(om,invec[i],(1+pt))); outvec; };
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; };
A020639(n) = if(n>1, if(n>n=factor(n, 0)[1, 1], n, factor(n)[1, 1]), 1); \\ From A020639
A032742(n) = (n/A020639(n));
v078898 = ordinal_transform(vector(up_to,n,A020639(n)));
A078898(n) = v078898[n];
A302042(n) = if((1==n)||isprime(n),1,my(c = A078898(n), p = prime(-1+primepi(A020639(n))+primepi(A020639(c))), d = A078898(c), k=0); while(d, k++; if((1==k)||(A020639(k)>=p),d -= 1)); (k*p));
A323888aux(n) = if(1==n, 0, [A032742(n),A302042(n)]);
v323888 = rgs_transform(vector(up_to, n, A323888aux(n)));
A323888(n) = v323888[n];