A331823 Positive numbers k such that -k, -(k + 1), and -(k + 2) are 3 consecutive negative negabinary-Niven numbers (A331728).

2, 8, 32, 54, 114, 128, 174, 234, 294, 370, 413, 414, 474, 512, 534, 580, 654, 774, 894, 954, 1000, 1014, 1134, 1430, 1734, 1794, 1840, 1854, 1914, 1974, 2034, 2048, 2093, 2094, 2154, 2214, 2334, 2574, 2680, 2694, 2814, 2870, 3054, 3100, 3520, 3773, 3774, 3834

Offset

1,1

Links

Amiram Eldar, Table of n, a(n) for n = 1..10000

Mathematica

negaBinWt[n_] := negaBinWt[n] = If[n == 0, 0, negaBinWt[Quotient[n - 1, -2]] + Mod[n, 2]]; negaBinNivenQ[n_] := Divisible[n, negaBinWt[-n]]; nConsec = 3; neg = negaBinNivenQ /@ Range[nConsec]; seq = {}; c = 0; k = nConsec+1; While[c < 50, If[And @@ neg, c++; AppendTo[seq, k - nConsec]]; neg = Join[Rest[neg], {negaBinNivenQ[k]}]; k++]; seq

Crossrefs

Cf. A005352, A027615, A039724, A154701, A328210, A328214, A330932, A331087, A331090, A331728, A331819, A331822.

Sequence in context: A071389 A026369 A269818 * A006552 A134753 A212892

Adjacent sequences: A331820 A331821 A331822 * A331824 A331825 A331826

Keyword

nonn,base

Author

Amiram Eldar, Jan 27 2020

Status

approved