A318648 Lexicographically first sequence of distinct nonnegative terms whose succession of digits is the same as in its associated sequence T (see the Comments section for T).

21, 10, 1, 910, 11, 8, 2, 91, 71, 12, 78, 9, 210, 22, 5, 3, 61, 13, 710, 211, 14, 101, 23, 32, 92, 15, 24, 610, 25, 6, 81, 93, 911, 212, 110, 26, 31, 16, 921, 102, 213, 33, 711, 103, 214, 27, 1010, 17, 221, 28, 18, 310, 29, 3110, 19, 111, 104, 222, 105, 62, 4, 51, 1110, 106, 41, 121, 107, 611, 231, 215, 216, 52, 82, 131

Offset

1,1

Comments

T(n) is the sum [last digit of a(n) + first digit of a(n+1)].

Links

Lars Blomberg, Table of n, a(n) for n = 1..3999

Example

The sequence starts with 21, 10, 1, 910, 11, 8, 2, 91, 71, 12, ...
Let's make the successive sums of [the last digit of a(n) + the first digit of a(n+1)]; we have [1+1] = 2; then [0+1] = 1; then [1+9] = 10; then [0+1] = 1; then [1+8] = 9; then [8+2] = 10; then [2+9] = 11; then [1+7] = 8; then [1+1] = 2; etc.
Those successive sums build the sequence T = 2, 1, 10, 1, 9, 10, 11, 8, 2, ... and T shows indeed the same succession of digits as the starting sequence.

Crossrefs

Cf. A318647 for the product (instead of the sum) of the digits "framing a comma" in the sequence.

Sequence in context: A220132 A146375 A040423 * A033341 A252629 A213217

Adjacent sequences: A318645 A318646 A318647 * A318649 A318650 A318651

Keyword

base,nonn

Author

Eric Angelini and Jean-Marc Falcoz, Aug 31 2018

Status

approved