The On-Line Encyclopedia of Integer Sequences (OEIS)

A240075 revision #15

A240075

Lexicographically earliest nonnegative increasing sequence such that no four terms have constant second differences.

0, 1, 2, 4, 5, 8, 15, 16, 17, 20, 44, 51, 52, 53, 56, 58, 64, 78, 166, 167, 192, 195, 196, 200, 202, 203, 206, 217, 226, 248, 249, 276, 312, 649, 657, 678, 681, 682, 715, 726, 740, 743, 747, 750, 771, 790, 830, 833, 836, 838, 842, 854, 875, 908, 911, 971

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OFFSET

1,3

LINKS

Vincenzo Librandi and T. D. Noe, Table of n, a(n) for n = 1..755 (first 123 terms from Vincenzo Librandi)

MATHEMATICA

t = {0, 1, 2}; Do[s = Table[Append[i, n], {i, Subsets[t, {3}]}]; If[! MemberQ[Flatten[Table[Differences[i, 3], {i, s}]], 0], AppendTo[t, n]], {n, 3, 1000}]; t

CROSSREFS

For the positive sequence, see A240555, which is this sequence plus 1.

Cf. A005836 (no 3-term starting at 0), A003278 (no 3-term starting at 1).

Cf. A240556, A240557.

Sequence in context: A226791 A357177 A184775 * A272229 A229083 A194415

Adjacent sequences: A240072 A240073 A240074 * A240076 A240077 A240078

KEYWORD

nonn

AUTHOR

T. D. Noe, Apr 09 2014

EXTENSIONS

Definition corrected by N. J. A. Sloane, Jan 04 2016.

STATUS

approved