A322806 Lexicographically earliest such sequence a that a(i) = a(j) => A285330(i) = A285330(j) for all i, j.

1, 2, 3, 3, 4, 5, 6, 4, 5, 7, 8, 9, 10, 11, 9, 6, 12, 13, 14, 15, 15, 16, 17, 18, 7, 19, 11, 20, 21, 22, 23, 8, 18, 24, 13, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 22, 38, 39, 40, 41, 42, 29, 43, 44, 45, 46, 47, 48, 49, 50, 10, 37, 51, 52, 28, 53, 54, 55, 56, 57, 58, 59, 60, 25, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 38

Offset: 1

Author

Antti Karttunen, Dec 26 2018

Keywords

• nonn

Comments

Restricted growth sequence transform of A285330.

Links

• Antti Karttunen, Table of n, a(n) for n = 1..65537

Crossrefs

Cf. A048675, A285328, A285330, A285332, A285333, A286543, A322807.

Programs

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; };
A007947(n) = factorback(factorint(n)[, 1]); \\ From A007947
A048675(n) = my(f = factor(n)); sum(k=1, #f~, f[k, 2]*2^primepi(f[k, 1]))/2; \\ From A048675
A285328(n) = { my(r); if((n > 1 && !bitand(n,(n-1))), (n/2), r=A007947(n); if(r==n,1,n = n-r; while(A007947(n) <> r, n = n-r); n)); };
A285330(n) = if(issquarefree(n),A048675(n),A285328(n));
v322806 = rgs_transform(vector(up_to,n,A285330(n)));
A322806(n) = v322806[n];