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A056928
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Average of smallest prime greater than n^2 and largest prime less than n^2.
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4
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4, 9, 15, 26, 34, 50, 64, 81, 99, 120, 144, 170, 195, 225, 254, 288, 324, 363, 399, 441, 483, 532, 574, 625, 675, 730, 780, 846, 897, 960, 1026, 1089, 1158, 1226, 1294, 1370, 1443, 1517, 1599, 1681, 1768, 1854, 1941, 2022, 2121, 2210, 2303, 2405, 2490
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history;
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OFFSET
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2,1
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LINKS
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Hugo Pfoertner, Table of n, a(n) for n = 2..10000
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FORMULA
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a(n) = (A007491(n) - A053001(n))/2.
a(n) = A000290(n) + (A053000(n)-A056927(n))/2.
a(n) = A000290(n) - A056929(n).
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EXAMPLE
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a(4)=15 because smallest prime greater than 4^2 is 17, largest prime less than 4^2 is 13 and average of 17 and 13 is 15
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MATHEMATICA
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Table[n2=n^2; (NextPrime[n2, -1]+NextPrime[n2])/2, {n, 2, 100}] (* Vladimir Joseph Stephan Orlovsky, Mar 09 2011*)
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PROG
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(PARI) a(n) = (nextprime(n^2) + precprime(n^2))/2; \\ Michel Marcus, May 20 2018
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CROSSREFS
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Cf. A007491, A053000, A053001, A056927, A056929, A056930, A056931.
Sequence in context: A030664 A070160 A244672 * A225283 A122964 A301254
Adjacent sequences: A056925 A056926 A056927 * A056929 A056930 A056931
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KEYWORD
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easy,nonn
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AUTHOR
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Henry Bottomley, Jul 12 2000
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STATUS
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approved
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