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A322824
Lexicographically earliest such sequence a that a(i) = a(j) => f(i) = f(j) for all i, j, where f(n) = 0 if n is an odd prime, and f(n) = A242424(n) for all other numbers.
2
1, 2, 3, 4, 3, 5, 3, 6, 7, 8, 3, 9, 3, 10, 11, 12, 3, 13, 3, 10, 14, 15, 3, 16, 17, 18, 19, 20, 3, 14, 3, 21, 22, 23, 24, 25, 3, 26, 27, 15, 3, 28, 3, 29, 30, 31, 3, 32, 33, 24, 34, 35, 3, 36, 37, 29, 38, 39, 3, 22, 3, 40, 41, 42, 43, 44, 3, 45, 46, 33, 3, 47, 3, 48, 49, 50, 51, 52, 3, 18, 53, 54, 3, 44, 55, 56, 57, 58, 3, 59, 60, 61, 62, 63, 64, 65, 3, 66, 67, 37, 3
OFFSET
1,2
COMMENTS
For all i, j: a(i) = a(j) => A087436(i) = A087436(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; };
A064989(n) = {my(f); f = factor(n); if((n>1 && f[1, 1]==2), f[1, 2] = 0); for (i=1, #f~, f[i, 1] = precprime(f[i, 1]-1)); factorback(f)};
A242424(n) = if(1==n, n, prime(bigomega(n))*A064989(n));
A322824aux(n) = if((n>2)&&isprime(n), 0, A242424(n));
v322824 = rgs_transform(vector(up_to, n, A322824aux(n)));
A322824(n) = v322824[n];
CROSSREFS
KEYWORD
nonn
AUTHOR
Antti Karttunen, Dec 29 2018
STATUS
approved