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A213307 revision #9

A213307

Minimal prime with n nonprime substrings (Version 3: substrings with leading zeros are counted as nonprime if the corresponding number is not a prime).

2, 13, 11, 127, 101, 149, 1009, 1063, 1049, 1481, 10091, 10069, 10169, 11681, 14669, 100129, 100189, 100169, 101681, 104681, 146669, 1000669, 1001219, 1001081, 1004669, 1014469, 1046849, 1468469, 10001081, 10004669, 10010851

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OFFSET

0,1

LINKS

Hieronymus Fischer, Table of n, a(n) for n = 0..100

FORMULA

a(n) > 10^floor((sqr(8*n+1)-1)/2), for n>2.

a(n) >= A213304(n).

a(n) >= A213306(n).

EXAMPLE

a(0) = 2, since 2 is the least number with zero nonprime substrings.

a(1) = 13, since 13 there is one nonprime substring (=1).