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A094189
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Number of primes between n^2-n and n^2 (inclusive).
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5
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0, 2, 1, 1, 1, 1, 2, 2, 2, 1, 1, 2, 3, 2, 2, 2, 3, 4, 4, 3, 4, 3, 3, 4, 5, 4, 3, 4, 5, 4, 4, 5, 4, 4, 5, 5, 2, 6, 6, 5, 4, 6, 4, 5, 7, 7, 3, 7, 8, 4, 5, 10, 7, 5, 6, 5, 5, 10, 7, 8, 8, 6, 10, 7, 5, 5, 8, 7, 7, 5, 10, 7, 8, 10, 7, 7, 10, 10, 9, 12, 7, 11, 10, 10, 9, 7, 13, 11, 10, 10, 11, 10, 11, 10, 11
(list; graph; refs; listen; history; internal format)
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OFFSET
| 1,2
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COMMENTS
| Conjecture: for n>11, a(n)>1.
Oppermann conjectured in 1882 that a(n)>0 for n>1. - T. D. Noe, Sep 16 2008
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REFERENCES
| Paulo Ribenboim, The New Book of Prime Number Records, 3rd ed., 1995, Springer, p. 248.
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LINKS
| T. D. Noe, Table of n, a(n) for n=1..10000
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PROG
| (PARI) a(n) = sum(k=n^2-n, n^2, isprime(k))
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CROSSREFS
| Cf. A014085, A089610, A108309
Sequence in context: A108244 A124961 A008967 * A122771 A112190 A112188
Adjacent sequences: A094186 A094187 A094188 * A094190 A094191 A094192
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KEYWORD
| easy,nonn
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AUTHOR
| Jason Earls (zevi_35711(AT)yahoo.com), May 25 2004
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