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A192451
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Number of primes between successive hexagonal numbers.
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1
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0, 3, 3, 3, 5, 4, 6, 6, 6, 6, 8, 8, 8, 8, 10, 10, 8, 12, 12, 11, 12, 11, 14, 14, 12, 16, 10, 16, 17, 15, 16, 15, 19, 14, 20, 16, 19, 20, 18, 15, 21, 20, 23, 21, 21, 22, 22, 21, 23, 21, 25, 22, 26, 23, 26, 25, 28, 23, 28, 27, 24
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OFFSET
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1,2
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LINKS
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FORMULA
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EXAMPLE
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There are no primes between 0 and 1, so a(1) = 0;
there are three primes between 1 and 6, so a(2) = 3;
there are three primes between 6 and 15, so a(3) = 3.
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MAPLE
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A192451 := proc(n) numtheory[pi](n*(2*n-1)) -numtheory[pi]((n-1)*(2*n-3)) ; end proc: # R. J. Mathar, Jul 01 2011
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PROG
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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