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A113901
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Product of omega(n) and bigomega(n) = A001221(n)*A001222(n), where omega(x): number of distinct prime divisors of x. bigomega(x): number of prime divisors of x, counted with multiplicity.
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15
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0, 1, 1, 2, 1, 4, 1, 3, 2, 4, 1, 6, 1, 4, 4, 4, 1, 6, 1, 6, 4, 4, 1, 8, 2, 4, 3, 6, 1, 9, 1, 5, 4, 4, 4, 8, 1, 4, 4, 8, 1, 9, 1, 6, 6, 4, 1, 10, 2, 6, 4, 6, 1, 8, 4, 8, 4, 4, 1, 12, 1, 4, 6, 6, 4, 9, 1, 6, 4, 9, 1, 10, 1, 4, 6, 6, 4, 9, 1, 10, 4, 4, 1, 12, 4, 4, 4, 8, 1, 12, 4, 6, 4, 4, 4, 12, 1, 6, 6, 8, 1, 9
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OFFSET
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1,4
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COMMENTS
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a(n) = 1 iff n is prime.
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LINKS
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MATHEMATICA
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Table[PrimeNu[n]*PrimeOmega[n], {n, 1, 50}] (* G. C. Greubel, Apr 23 2017 *)
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PROG
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(PARI) list(n) = { local(x); for(x=1, n, print1(omega(x)*bigomega(x)", ") ) }
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CROSSREFS
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A307409(n) is (bigomega(n) - 1) * omega(n).
A328958(n) is sigma_0(n) - bigomega(n) * omega(n).
Cf. A000005, A001221, A001222, A060687, A070175, A071625, A124010, A303555, A320632, A323023, A328956, A328957, A328964, A328965.
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KEYWORD
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easy,nonn
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AUTHOR
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STATUS
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approved
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