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A066612
Number of primes between n^n and (n+1)^(n+1).
0
2, 7, 45, 391, 4376, 60864, 1012186, 19622935, 434351705, 10807060863, 298525056829, 9063891473730, 300004447041493, 10750198453038838, 414596707456493479, 17122019740329088733, 753855850836114017867, 35248703133243910547502
OFFSET
1,1
EXAMPLE
a(2) = 7 as there are 7 primes between 2^2 (= 4) and 3^3 (= 27) namely 5, 7, 11, 13, 17, 19, and 23.
MATHEMATICA
Table[PrimePi[(k+1)^(k+1)]-PrimePi[k^k], {k, 12}](* Vladimir Joseph Stephan Orlovsky, Nov 30 2010 *)
CROSSREFS
Equals first differences of A064151.
Sequence in context: A064606 A331711 A223001 * A098637 A162045 A326878
KEYWORD
nonn
AUTHOR
Amarnath Murthy, Dec 24 2001
EXTENSIONS
Corrected and extended by Robert G. Wilson v, Dec 26 2001
a(12)-a(14) from Donovan Johnson, Oct 14 2010
a(15)-a(18) from Amiram Eldar, Jun 11 2024
STATUS
approved