OFFSET
1,6
COMMENTS
Ordinal transform of A034684.
LINKS
Antti Karttunen, Table of n, a(n) for n = 1..65537
MATHEMATICA
A034684[n_] := With[{f = FactorInteger[n]}, Min[f[[All, 1]]^f[[All, 2]]]];
Module[{b}, b[_] = 0;
a[n_] := With[{t = A034684[n]}, b[t] = b[t] + 1]];
Array[a, 105] (* Jean-François Alcover, Jan 10 2022 *)
PROG
(PARI)
up_to = 65537;
A034684(n) = if(1==n, n, my(f=factor(n)); vecmin(vector(#f[, 1], i, f[i, 1]^f[i, 2]))); \\ After code in A034699
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; };
v330755 = ordinal_transform(vector(up_to, n, A034684(n)));
A330755(n) = v330755[n];
CROSSREFS
KEYWORD
nonn
AUTHOR
Antti Karttunen, Dec 30 2019
STATUS
approved