A098953 Slowest increasing sequence where each number is such that at least one pair of adjacent digits are consecutive, the first of the pair being the smaller.

12, 23, 34, 45, 56, 67, 78, 89, 101, 112, 120, 121, 122, 123, 124, 125, 126, 127, 128, 129, 134, 145, 156, 167, 178, 189, 201, 212, 223, 230, 231, 232, 233, 234, 235, 236, 237, 238, 239, 245, 256, 267, 278, 289, 301, 312, 323, 334, 340, 341, 342, 343, 344, 345

Offset

1,1

Comments

Corrected by Zak Seidov, Apr 15 2007

Links

Michael S. Branicky, Table of n, a(n) for n = 1..10000

Prog

(Python)
from itertools import count, islice
def cond(n):
    d = list(map(int, str(n)))
    return any(d[i+1] == d[i]+1 for i in range(len(d)-1))
def agen():
    yield from filter(cond, count(1))
print(list(islice(agen(), 54))) # Michael S. Branicky, Dec 23 2021

Crossrefs

A similar sequence: A082927

Sequence in context: A136414 A017401 A004960 * A228157 A363820 A072485

Adjacent sequences: A098950 A098951 A098952 * A098954 A098955 A098956

Keyword

base,easy,nonn

Author

Eric Angelini, Oct 21 2004

Extensions

a(51) and beyond from Michael S. Branicky, Dec 23 2021

Status

approved