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a(n) > 10^floor((sqrsqrt(8*n+1)-1)/2), for n>2.
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a(0) = 2, since 2 is the least number with zero nonprime substrings.
a(1) = 13, since 13 there is one nonprime substring (=1).
a(2) = 11, since 11 is the least number with 2 nonprime substrings (2 times ‘1’).
a(3) = 127, since 127 is the least number with 3 nonprime substrings, these are 1 and 12 and 27 (according to version 3).
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, 10010849, 10014469, 10166699, 10444849
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Minimal prime with n non-prime nonprime substrings (Version 3: substrings with leading zeros are counted as non-prime nonprime if the corresponding number is not a prime).
a(0)=2, since 2 is the least number with zero non-prime nonprime substrings.
a(1)=13, since 13 there is one non-prime nonprime substring (=1).
a(2)=11, since 11 is the least number with 2 non-prime nonprime substrings (2 times ‘1’).
a(3)=127, since 127 is the least number with 3 non-prime nonprime substrings, these are 1 and 12 and 27 (according to version 3).
nonn,changed,base
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