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A333053
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Numbers m such that min(d(m), d(m+1)) > min(d(k), d(k+1)) for all k < m, where d(m) is the number of divisors of m (A000005).
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1
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1, 2, 8, 14, 44, 104, 224, 495, 735, 2024, 2079, 5264, 5984, 21735, 126224, 201824, 862784, 1890944, 2821455, 6116175, 7316000, 14753024, 23014719, 38127375, 80061344, 205466624, 391738599, 879207615, 1794220064, 3199900599, 3809727999, 16916370624
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OFFSET
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1,2
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COMMENTS
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The corresponding values of min(d(a(n)), d(a(n)+1)) are 1, 2, 3, 4, 6, 8, 9, 10, 12, 15, 16, 20, 24, 32, 40, 48, 56, 64, 72, 80, 96, 108, 112, 120, 144, 160, 192, 224, 240, 256, 288, 320, ...
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LINKS
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EXAMPLE
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The values of min(d(k), d(k+1)) for k = 1, 2, ... 8 are 1, 2, 2, 2, 2, 2, 2, 3. The record values in this range, 1, 2 and 3, are obtained at k = 1, 2, and 8.
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MATHEMATICA
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seq={}; dminmax = 0; d1 = 1; Do[d2 = DivisorSigma[0, n]; dmin = Min[d1, d2]; If[dmin > dminmax, dminmax = dmin; AppendTo[seq, n-1]]; d1 = d2, {n, 2, 10^6}]; seq
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CROSSREFS
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KEYWORD
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nonn,more
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AUTHOR
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STATUS
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approved
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