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A322868 Lexicographically earliest such sequence a that a(i) = a(j) => A278222(A048675(i)) = A278222(A048675(j)) for all i, j. 3
1, 2, 2, 2, 2, 3, 2, 3, 2, 4, 2, 2, 2, 4, 3, 2, 2, 4, 2, 3, 4, 4, 2, 4, 2, 4, 3, 4, 2, 5, 2, 4, 4, 4, 3, 3, 2, 4, 4, 5, 2, 6, 2, 4, 2, 4, 2, 3, 2, 4, 4, 4, 2, 5, 4, 6, 4, 4, 2, 2, 2, 4, 3, 3, 4, 6, 2, 4, 4, 6, 2, 5, 2, 4, 4, 4, 3, 6, 2, 2, 2, 4, 2, 3, 4, 4, 4, 6, 2, 4, 4, 4, 4, 4, 4, 5, 2, 4, 4, 4, 2, 6, 2, 6, 5 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,2
COMMENTS
Restricted growth sequence transform of A278222(A048675(n)), or equivalently, of A278222(A322821(n)).
For all i, j: a(i) = a(j) => A322869(i) = A322869(j).
LINKS
PROG
(PARI)
up_to = 8192;
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; };
A005940(n) = { my(p=2, t=1); n--; until(!n\=2, if((n%2), (t*=p), p=nextprime(p+1))); t };
A046523(n) = { my(f=vecsort(factor(n)[, 2], , 4), p); prod(i=1, #f, (p=nextprime(p+1))^f[i]); }; \\ From A046523
A048675(n) = { my(f = factor(n)); sum(k=1, #f~, f[k, 2]*2^primepi(f[k, 1]))/2; }; \\ From A048675
A278222(n) = A046523(A005940(1+n));
v322868 = rgs_transform(vector(up_to, n, A278222(A048675(n))));
A322868(n) = v322868[n];
CROSSREFS
Sequence in context: A341829 A344888 A216325 * A240975 A242166 A068211
KEYWORD
nonn
AUTHOR
Antti Karttunen, Dec 31 2018
STATUS
approved

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Last modified April 19 02:45 EDT 2024. Contains 371782 sequences. (Running on oeis4.)