A309706 - OEIS

A309706

Smallest number that contains the first n primes as substrings in base 10. Substrings go from left to right, but numbers in the substrings can be separated by several numbers.

2, 23, 235, 2357, 112357, 112357, 112357, 1123579, 1123579, 1123579, 1231579, 1231579, 12341579, 12431579, 12431579, 12453179, 12453179, 124536179, 124536179, 1124536719, 1234567139, 1234567139, 12345671839, 12345671839, 12456783197, 102456783197, 102456783197, 102456783197

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OFFSET

1,1

COMMENTS

The version with subsequences of contiguous numbers is A054261.

The sequence is nondecreasing, by definition.

LINKS

Table of n, a(n) for n=1..28.

FORMULA

a(n) <= A054261(n). - David A. Corneth, Aug 28 2019

EXAMPLE

The series starts as A054261, but 112357 is followed by 112357 because 13 can be obtained with a subsequence '1','3' which is interrupted by '2'.