A361336 Smallest decimal number containing n palindromic substrings (Version 2). See Comments for precise definition.

0, 10, 11, 100, 1002, 111, 1000, 10002, 10001, 1111, 10000, 100002, 100001, 1000012, 11111, 100000, 1000002, 1000001, 10000012, 10000010, 111111, 1000000, 10000002, 10000001, 100000012, 100000010, 110111111, 1111111, 10000000, 100000002, 100000001, 1000000012, 1000000010

Offset

1,2

Comments

Suppose m has decimal expansion d_1 d_2 ... d_k. A palindromic substring here is any substring d_i, d_{i+1}, ..., d_j with 1 <= i <= j <= n which is palindromic. In this version d_i can be 0 even if j>i. For example, if m = 10^3 + 1 = 1001 there are six substrings: 1, 0, 0, 1, 00, and 1001. See A361335 for Version 1.

Links

Giovanni Resta, Table of n, a(n) for n = 1..99

Crossrefs

Cf. A361335.

Sequence in context: A171782 A038313 A066330 * A348109 A125099 A055611

Adjacent sequences: A361333 A361334 A361335 * A361337 A361338 A361339

Keyword

nonn,base

Author

N. J. A. Sloane, Apr 01 2023, based on postings to the Sequence Fans Mailing list by Eric Angelini, Mar 28 2023 (definition), and Giovanni Resta, Mar 28 2023 (terms)

Status

approved