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A339902
Number of prime divisors of A339821(n), counted with multiplicity.
2
0, 1, 2, 3, 2, 3, 4, 5, 2, 3, 4, 5, 4, 5, 6, 7, 3, 4, 5, 6, 5, 6, 7, 8, 5, 6, 7, 8, 7, 8, 9, 10, 4, 5, 6, 7, 6, 7, 8, 9, 6, 7, 8, 9, 8, 9, 10, 11, 7, 8, 9, 10, 9, 10, 11, 12, 9, 10, 11, 12, 11, 12, 13, 14, 3, 4, 5, 6, 5, 6, 7, 8, 5, 6, 7, 8, 7, 8, 9, 10, 6, 7, 8, 9, 8, 9, 10, 11, 8, 9, 10, 11, 10, 11, 12, 13, 7
OFFSET
0,3
FORMULA
If 4n = 2^e1 + 2^e2 + ... + 2^ek [e1 ... ek distinct], then a(n) = A023508(e1) + A023508(e2) + ... + A023508(ek).
a(n) = A001222(A339821(n)).
a(n) >= A339822(n).
PROG
(PARI) A339902(n) = { my(s=0, p=2); while(n>0, p = nextprime(1+p); if(n%2, s += bigomega(p-1)); n >>= 1); (s); };
KEYWORD
nonn
AUTHOR
Antti Karttunen, Dec 21 2020
STATUS
approved