A365258 The four digits of a(n), their three successive absolute first differences and their two successive absolute second differences are all distinct.

2983, 3892, 4197, 4917, 5298, 5928, 7194, 7398, 7914, 7938, 8139, 8295, 8329, 8397, 8925, 8937, 9238, 9318

Offset

1,1

Comments

The digit 0 is never present in a(n) and never appears as a first or a second difference (as this would duplicate in both cases one of the 8 remaining digits involved).

The sequence ends with a(18) = 9318.

Links

Table of n, a(n) for n=1..18.

Example

2983 is a term since its three successive absolute first differences 7 (= 2 - 9), 1 (= 9 - 8), 5 (= 8 - 3) and the successive absolute second differences 6 (= 7 - 1) and 4 (= 1 - 5), are nine distinct digits.
  2 9 8 3
   7 1 5
    6 4

Mathematica

Select[Range[1000, 9999], Sort@Join[IntegerDigits@#, s=Abs@Differences@IntegerDigits@#, Abs@Differences@s]==Range@9&]

Crossrefs

Cf. A365257, A100787, A040114, A270263.

Sequence in context: A235744 A235503 A120373 * A186866 A252571 A231628

Adjacent sequences: A365255 A365256 A365257 * A365259 A365260 A365261

Keyword

base,nonn,fini,full

Author

Eric Angelini and Giorgos Kalogeropoulos, Aug 29 2023

Status

approved