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A273285
A273283(n)^Omega(n), where Omega = A001222.
5
2, 3, 4, 5, 9, 7, 8, 9, 25, 11, 27, 13, 25, 25, 16, 17, 27, 19, 27, 25, 25, 23, 81, 25, 49, 27, 125, 29, 125, 31, 32, 49, 49, 49, 81, 37, 49, 49, 81, 41, 125, 43, 125, 125, 49, 47, 243, 49, 125, 121, 125, 53, 81, 121, 81, 121, 121, 59, 81, 61, 121, 125, 64, 121, 125, 67, 125, 121, 125, 71
OFFSET
2,1
COMMENTS
a(n) >= A079871(n) for any n>=2.
a(n) = n iff n is the power of a prime (A246655).
LINKS
FORMULA
a(n) = A273283(n)^A001222(n).
EXAMPLE
a(33) = 49 because Omega(33)=2 and 5^2 < 33 < 7^2.
a(2403) = 11^4 (and A273284(2403)=7^4) because A001222(3^3*89)=4 and 7^4 < n < 11^4.
MATHEMATICA
Table[NextPrime[(Ceiling[n^(1/PrimeOmega[n])] - 1)]^PrimeOmega[n], {n, 2, 50}] (* G. C. Greubel, May 26 2016 *)
PROG
(Sage) s=sloane.A001222; [next_prime(ceil(n^(1/s(n)))-1)^s(n) for n in (2..82)]
CROSSREFS
KEYWORD
nonn
AUTHOR
Giuseppe Coppoletta, May 20 2016
STATUS
approved