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A323367
Lexicographically earliest such sequence a that for all i, j, a(i) = a(j) => f(i) = f(j), where f(n) = 0 for odd primes, and f(n) = A323366(n) for any other number.
5
1, 2, 3, 4, 3, 5, 3, 6, 7, 8, 3, 9, 3, 10, 11, 12, 3, 13, 3, 14, 15, 16, 3, 17, 18, 19, 20, 21, 3, 22, 3, 23, 24, 25, 26, 27, 3, 28, 26, 29, 3, 19, 3, 30, 31, 32, 3, 33, 34, 35, 36, 37, 3, 38, 39, 40, 41, 42, 3, 43, 3, 44, 45, 46, 47, 48, 3, 49, 50, 51, 3, 52, 3, 53, 54, 55, 56, 51, 3, 57, 58, 59, 3, 37, 60, 61, 62, 63, 3, 64, 65, 66, 56, 67, 65, 68, 3, 69, 70, 71, 3, 72, 3, 73, 47
OFFSET
1,2
COMMENTS
Restricted growth sequence transform of function f, where f(n) = 0 for odd primes, and for any other number, f(n) = [A000035(n), A003557(n), A173557(n)].
For all i, j:
A305801(i) = A305801(j) => a(i) = a(j),
a(i) = a(j) => A007814(i) = A007814(j),
a(i) = a(j) => A322587(i) = A322587(j).
a(i) = a(j) => A323237(i) = A323237(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; };
A003557(n) = { my(f=factor(n)); for(i=1, #f~, f[i, 2] = f[i, 2]-1); factorback(f); };
A173557(n) = my(f=factor(n)[, 1]); prod(k=1, #f, f[k]-1); \\ From A173557
Aux323367(n) = if((n>2)&&isprime(n), 0, [(n%2), A003557(n), A173557(n)]);
v323367 = rgs_transform(vector(up_to, n, Aux323367(n)));
A323367(n) = v323367[n];
CROSSREFS
KEYWORD
nonn
AUTHOR
Antti Karttunen, Jan 12 2019
STATUS
approved