OFFSET

1,2

COMMENTS

A generalization of A121805.

LINKS

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

EXAMPLE

a(1) = 1, so ef = "01" = 1. So v-u will be a four-digit number (with a leading zero in this case), say v-u = 0xyz, with v = 1 + xyz. This suggests that we try x=1 and y=1, v = 1 + xyz = 1 + 11*, where * = 1+z. The smallest choice is z = 0, giving "efhi" = "0111" = 111, and a(2) = 1 + 111 = 112 works.

PROG

(Python)

from itertools import islice

def agen(): # generator of terms

an, y = 1, 1

while y:

yield an

an, y = an + 100*(an%100), 1

y = next((y for y in range(1, 100) if str(an+y)[:2] == str(y)), 0)

an += y

print(list(islice(agen(), 36))) # Michael S. Branicky, Nov 23 2023

CROSSREFS

KEYWORD

nonn,base

AUTHOR

N. J. A. Sloane, Nov 23 2023

EXTENSIONS

More terms from Michael S. Branicky, Nov 23 2023

STATUS

approved