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A188631
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Numbers k such that d(k-1) < d(k) < d(k+1) where d(k) is the number of divisors of k.
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2
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62, 63, 74, 164, 188, 194, 195, 207, 255, 275, 278, 279, 284, 314, 356, 362, 363, 398, 399, 404, 422, 423, 428, 455, 458, 459, 483, 494, 524, 539, 584, 614, 615, 662, 674, 692, 734, 747, 758, 759, 764, 824, 854, 867, 890, 927, 935, 944, 956, 998, 999
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OFFSET
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1,1
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LINKS
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FORMULA
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MATHEMATICA
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Select[Range[2, 1000], DivisorSigma[0, # - 1] < DivisorSigma[0, #] < DivisorSigma[0, # + 1] &] (* T. D. Noe, Apr 05 2011 *)
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PROG
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(Magma) d:=func<k | NumberOfDivisors(k)>; [ n: n in [2..1000] | d(n-1) lt d(n) and d(n) lt d(n+1)]; // Bruno Berselli, Apr 05 2011
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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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Corrected and extended by T. D. Noe, Apr 05 2011
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STATUS
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approved
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