A060555 String together the first n numbers in an order which minimizes the result.

1, 12, 123, 1234, 12345, 123456, 1234567, 12345678, 123456789, 10123456789, 1011123456789, 101111223456789, 10111121323456789, 1011112131423456789, 101111213141523456789, 10111121314151623456789

Offset: 1

Author

Henry Bottomley, Apr 02 2001

Keywords

• base
• easy
• nonn

Crossrefs

Cf. A000422, A060554.

Programs

Python

from itertools import count, islice
def agen(): # generator of terms
    slst = []
    for n in count(1):
        s, least, argleast = str(n), ":", None
        for i in range(len(slst)+1):
            t = "".join(slst[:i]) + s + "".join(slst[i:])
            if t < least: least, argleast = t, i
        slst.insert(argleast, s)
        yield int("".join(slst))
print(list(islice(agen(), 16))) # Michael S. Branicky, Nov 29 2022

Extensions

Incorrect comment removed by Sean A. Irvine, Nov 30 2022