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A368855
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Index of the first occurrence of n in A076982.
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1
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1, 2, 3, 8, 14, 15, 39, 20, 44, 35, 195, 119, 104, 594, 224, 384, 455, 539, 440, 560, 3080, 2184, 1539, 2015, 2639, 5264, 4199, 15399, 13299, 8855, 23919, 2079, 30744, 43680, 36575, 14399, 5984, 58695, 113399, 47124, 107184, 12375, 78624, 98175, 73359, 111320, 242879, 185724
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OFFSET
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1,2
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LINKS
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FORMULA
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EXAMPLE
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a(5) = 14 since A076982(14) = 5; etc.
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MATHEMATICA
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k = 1; t[_] := 0; f[n_] := Length@ Select[ Divisors[n (n +1)/2], IntegerQ@ Sqrt[8# +1] &]; While[k < 250000, a = f@k; If[ t[a] == 0, t[a] = k]; k++]; t /@ Range@ 48
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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