A338855 Concatenating all successive absolute differences between two successive digits of a(n) produce a subchain of a(n).

10, 12, 20, 21, 24, 30, 36, 40, 42, 48, 50, 60, 63, 70, 80, 84, 90, 100, 120, 124, 200, 240, 248, 300, 360, 400, 421, 480, 500, 600, 700, 800, 842, 900, 1000, 1200, 1240, 1248, 2000, 2400, 2480, 3000, 3600, 4000, 4800, 5000, 6000, 7000, 8000, 8421, 9000, 10000, 12000, 12400, 12480, 20000, 24000, 24800, 30000

Offset

1,1

Comments

This is the lexicographically earliest sequence of distinct positive terms with this property.

Links

Table of n, a(n) for n=1..59.

Maple

a(1) = 10 is in the sequence because the absolute difference between 1 and 0 is 1, and 1 is a subchain of 10;
a(2) = 12 is in the sequence because the absolute difference between 1 and 2 is 1, and 1 is a subchain of 12;
a(3) = 20 is in the sequence because the absolute difference between 2 and 0 is 2, and 2 is a subchain of 20;
...
a(20) = 124; the absolute difference between 1 and 2 is 1; the absolute difference between 2 and 4 is 2; concatenating those differences produce 12 and 12 is a subchain of 124; etc.

Crossrefs

Cf. A338640 [the concatenation produces a divisor of a(n)], A338641 [the starting numbers have no duplicated digits and the concatenation is a divisor of a(n)].

Sequence in context: A129845 A075492 A225742 * A221638 A358998 A085772

Adjacent sequences: A338852 A338853 A338854 * A338856 A338857 A338858

Keyword

base,nonn

Author

Eric Angelini, Nov 12 2020

Status

approved