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A328577
Lexicographically earliest infinite sequence such that a(i) = a(j) => f(i) = f(j), where f(0) = 0 and f(n>0) = A328572(n), for all i, j.
3
1, 2, 2, 2, 3, 3, 2, 2, 2, 2, 3, 3, 4, 4, 4, 4, 5, 5, 6, 6, 6, 6, 7, 7, 8, 8, 8, 8, 9, 9, 2, 2, 2, 2, 3, 3, 2, 2, 2, 2, 3, 3, 4, 4, 4, 4, 5, 5, 6, 6, 6, 6, 7, 7, 8, 8, 8, 8, 9, 9, 10, 10, 10, 10, 11, 11, 10, 10, 10, 10, 11, 11, 12, 12, 12, 12, 13, 13, 14, 14, 14, 14, 15, 15, 16, 16, 16, 16, 17, 17, 18, 18, 18, 18, 19, 19, 18, 18, 18, 18, 19, 19, 20, 20, 20, 20
OFFSET
0,2
COMMENTS
Restricted growth sequence transform of function f, defined as: f(0) = 0 and for n > 0, f(n) = A328572(n) = A003557(A276086(n)).
For all i, j: a(i) = a(j) => A328114(i) = A328114(j).
PROG
(PARI)
up_to = 32768;
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; };
A328572(n) = { my(m=1, p=2); while(n, if(n%p, m *= p^((n%p)-1)); n = n\p; p = nextprime(1+p)); (m); };
Aux328577(n) = if(!n, n, A328572(n));
v328577 = rgs_transform(vector(1+up_to, n, Aux328577(n-1)));
A328577(n) = v328577[1+n];
CROSSREFS
KEYWORD
nonn
AUTHOR
Antti Karttunen, Oct 20 2019
STATUS
approved