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A101984
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Numbers that occur exactly once in A101909 (= count of primes between 2n and 4n).
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2
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1, 3, 5, 8, 22, 36, 37, 46, 47, 48, 53, 63, 83, 98, 99, 101, 105, 108, 113, 114, 127, 135, 139, 148, 150, 155, 158, 171, 172, 173, 174, 175, 177, 178, 188, 205, 210, 218, 219, 220, 221, 226, 231, 240, 246, 254, 277, 282, 297, 298, 301, 303, 327, 333, 334, 339
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OFFSET
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1,2
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LINKS
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EXAMPLE
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There are 5 primes between 16 and 32 and nowhere else between 2n and 4n.
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PROG
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(PARI) bet2n4n(n)={ my(b=vecsort(vector(n, x, my(c=0); forprime(y=2*x+1, 4*x-1, c++); c))); print1(1", "); for(x=1, n-2, if(b[x+1]>b[x] && b[x+1]<b[x+2], print1(b[x+1]", ")))} \\ Edited and corrected, following a suggestion by Don Reble. - M. F. Hasler, Sep 29 2019
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CROSSREFS
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KEYWORD
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easy,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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