A365257 -id:A365257 - cp's OEIS frontend

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

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Eric Angelini and Giorgos Kalogeropoulos, Aug 29 2023

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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.

			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

Cf. A365257, A100787, A040114, A270263.

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

cp's OEIS Frontend

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

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