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A322811
a(1) = 0; for n > 1, a(n) = A001221(A285330(n)).
3
0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 2, 1, 1, 2, 1, 1, 2, 1, 2, 2, 1, 1, 2, 1, 2, 1, 2, 1, 1, 1, 1, 2, 2, 2, 2, 1, 2, 2, 2, 1, 1, 1, 2, 2, 1, 1, 2, 1, 2, 3, 2, 1, 2, 2, 2, 3, 2, 1, 3, 1, 2, 2, 1, 2, 1, 1, 2, 3, 1, 1, 2, 1, 2, 2, 2, 2, 2, 1, 2, 1, 2, 1, 3, 2, 2, 2, 2, 1, 3, 2, 2, 3, 3, 3, 2, 1, 2, 2, 2, 1, 1, 1, 2, 2
OFFSET
1,12
COMMENTS
For all i, j:
A322806(i) = A322806(j) => a(i) = a(j),
A322807(i) = A322807(j) => a(i) = a(j).
LINKS
FORMULA
a(1) = 0; for n > 1, a(n) = A001221(A285330(n)).
If n > 1 is squarefree, a(n) = A322812(n) = A001221(A048675(n)), otherwise a(n) = A001221(A285328(n)) = A001221(n).
PROG
(PARI)
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));
A322811(n) = if(1==n, 0, omega(A285330(n)));
CROSSREFS
KEYWORD
nonn
AUTHOR
Antti Karttunen, Dec 27 2018
STATUS
approved