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A359317
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a(n) is the smallest tetrahedral number with binary weight n.
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1
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0, 1, 10, 35, 120, 220, 455, 2024, 1771, 4060, 14190, 16215, 129766, 32509, 1414910, 1823471, 5159805, 8171255, 4192244, 24117100, 30865405, 334985911, 192937325, 1610599145, 1048440315, 4261347265, 4244012991, 63828916911, 213588635511, 133110357279
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OFFSET
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0,3
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LINKS
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EXAMPLE
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455 is the smallest tetrahedral number with binary weight 6 (455_10 = 111000111_2), so a(6) = 455.
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MATHEMATICA
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seq[len_, nmax_] := Module[{s = Table[0, {len}], n = 0, c = 0, bw, t}, While[c < len && n < nmax, bw = DigitCount[t = n*(n+1)*(n+2)/6, 2, 1] + 1; If[bw <= len && s[[bw]] == 0, c++; s[[bw]] = t]; n++]; s]; seq[30, 10^6] (* Amiram Eldar, Dec 26 2022 *)
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CROSSREFS
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KEYWORD
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nonn,base
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AUTHOR
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STATUS
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approved
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