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A328472 Lexicographically earliest infinite sequence such that a(i) = a(j) => A278226(A328461(i)) = A278226(A328461(j)) for all i, j. 3
1, 1, 2, 1, 2, 3, 4, 1, 2, 5, 4, 1, 4, 6, 7, 1, 2, 8, 4, 2, 4, 9, 7, 2, 4, 10, 7, 11, 7, 12, 13, 1, 2, 14, 4, 15, 4, 16, 7, 17, 4, 18, 7, 19, 7, 20, 13, 3, 4, 21, 7, 22, 7, 23, 13, 24, 7, 25, 13, 22, 13, 26, 27, 1, 2, 28, 4, 29, 4, 30, 7, 20, 4, 31, 7, 32, 7, 33, 13, 34, 4, 35, 7, 36, 7, 37, 13, 38, 7, 39, 13, 36, 13, 40, 27, 22, 4 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,3
COMMENTS
Restricted growth sequence transform of function f(n) = A046523(A276086(A276156(n)/A002110(A007814(n)))).
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; };
A002110(n) = prod(i=1, n, prime(i));
A276156(n) = { my(p=2, pr=1, s=0); while(n, if(n%2, s += pr); n >>= 1; pr *= p; p = nextprime(1+p)); (s); };
A328461(n) = (A276156(n)/A002110(valuation(n, 2)));
A046523(n) = { my(f=vecsort(factor(n)[, 2], , 4), p); prod(i=1, #f, (p=nextprime(p+1))^f[i]); }; \\ From A046523
A276086(n) = { my(m=1, p=2); while(n, m *= (p^(n%p)); n = n\p; p = nextprime(1+p)); (m); };
v328472 = rgs_transform(vector(up_to, n, A278226(A328461(n))));
A328472(n) = v328472[n];
CROSSREFS
Sequence in context: A169778 A309776 A255560 * A046653 A308897 A353293
KEYWORD
nonn
AUTHOR
Antti Karttunen, Oct 18 2019
STATUS
approved

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Last modified May 24 23:50 EDT 2024. Contains 372782 sequences. (Running on oeis4.)