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A020948
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Least k such that b(k) = n, where b( ) is sequence A020944.
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4
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1, 8, 16, 32, 34, 128, 66, 68, 130, 134, 132, 140, 138, 260, 264, 284, 268, 266, 274, 572, 276, 524, 522, 536, 534, 530, 538, 1034, 532, 548, 556, 1046, 1042, 554, 1050, 1082, 1044, 2072, 1092, 1064, 1060, 2114, 1068, 1076, 1132, 1100, 1066, 2102, 1098, 1106, 2088, 2084, 2098, 4346, 1108
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OFFSET
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1,2
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LINKS
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MATHEMATICA
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a[n_] := a[n] = Which[n < 2, Boole[n == 1] - Boole[n == 0], OddQ[n], Abs[a[n - 1] - a[n - 2]], True, a[n/2] + a[n/2 - 1]]; s = Array[a[#] &, 4200]; Array[FirstPosition[s, #][[1]] &, LengthWhile[Differences@ Union@ s, # == 1 &]] (* Michael De Vlieger, Feb 18 2022, after Michael Somos at A020944 *)
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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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STATUS
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approved
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