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A335425
Lexicographically earliest infinite sequence such that a(i) = a(j) => A000188(i) = A000188(j) and A335424(i) = A335424(j) for all i, j >= 1.
3
1, 2, 2, 3, 2, 4, 2, 5, 6, 7, 2, 5, 2, 7, 4, 8, 2, 9, 2, 5, 7, 7, 2, 10, 11, 7, 9, 5, 2, 12, 2, 13, 7, 7, 4, 14, 2, 7, 7, 15, 2, 16, 2, 5, 9, 7, 2, 13, 17, 18, 7, 5, 2, 19, 7, 15, 7, 7, 2, 10, 2, 7, 9, 20, 7, 16, 2, 5, 7, 16, 2, 21, 2, 7, 18, 5, 4, 16, 2, 13, 22, 7, 2, 15, 7, 7, 7, 15, 2, 23, 7, 5, 7, 7, 7, 24, 2, 25, 9, 26, 2, 16, 2, 15, 12
OFFSET
1,2
COMMENTS
Restricted growth sequence transform of the ordered pair [A000188(n), A046523(A335423(n))].
For all i, j: A305800(i) = A305800(j) => a(i) = a(j) => A001222(i) = A001222(j).
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; };
A000188(n) = core(n, 1)[2]; \\ From A000188
A048675(n) = { my(f = factor(n)); sum(k=1, #f~, f[k, 2]*2^primepi(f[k, 1]))/2; };
A248663(n) = A048675(core(n));
A005940(n) = { my(p=2, t=1); n--; until(!n\=2, if((n%2), (t*=p), p=nextprime(p+1))); t };
A335423(n) = A005940(1+A248663(n));
A046523(n) = { my(f=vecsort(factor(n)[, 2], , 4), p); prod(i=1, #f, (p=nextprime(p+1))^f[i]); }; \\ From A046523
Aux335425(n) = [A000188(n), A046523(A335423(n))];
v335425 = rgs_transform(vector(up_to, n, Aux335425(n)));
A335425(n) = v335425[n];
KEYWORD
nonn
AUTHOR
Antti Karttunen, Jun 13 2020
STATUS
approved