1234567891

Appears in sequences

• Lengths increase by 1, digits cycle through positive digits.at n=9A007923
• Primes in A007923.at n=3A050234
• Smallest prime containing a leading sequence of n ascending numbers.at n=8A053546
• a(1) = 2; then the sequence of smallest primes (no zero digits to avoid ambiguity) not included earlier the concatenation of which is the cyclic pattern 23456789123456789123...at n=4A068826
• First occurrence of an n-digit prime as a substring in the concatenation of the natural numbers 12345678910111213141516171819202122232425262728293031....at n=9A073175
• Smallest number such that n*a(n) is a concatenation of n consecutive integers; or 0 if no such number exists.at n=9A075000
• a(1) = 1; for n>1, a(n) = the largest prime divisor of the number C(n) formed from the concatenation of 1,2,3,... up to n.at n=9A075022
• a(n) = floor({concatenation 123 ... up to n}/n).at n=9A077147
• a(n) = numerator(N), where N = 0.123...n (concatenation of 1 to n after decimal point).at n=9A078258
• Smallest prime of the form the concatenation r*k for r = 1 to n followed by a 1.at n=8A089328
• Natural numbers written out and then regrouped into the smallest possible nontrivial blocks such that each begins and ends with the same digit. (Leading zeros omitted and not counted as beginning digit).at n=0A091416
• Erroneous version of: Primes from merging of 10 successive digits in decimal expansion of the Champernowne constant.at n=0A104953
• Smallest prime with a run of n strictly increasing digits.at n=8A108471
• Smallest prime == 1 (mod f(n)), where f(n) = concatenation 1,2,3,... up to n.at n=8A109947
• Smallest prime of the form: n successive positive integers in ascending order followed by a 1.at n=8A114754
• Consider the infinite string S = 12345678910111213141516171819202122232425262728293031... Sequence gives the first prime that starts at the k-th digit, skipping zero digits.at n=0A135605
• Zeroless primes with consecutive digits (1,..,9) starting with 1.at n=0A154769
• Write the natural numbers as an infinite sequence of digits; starting at the left, cut into the smallest pieces so that each piece is a prime. Leading zeros are thrown away.at n=0A162324
• Smallest divisor of 123...n (=A007908) larger than the preceding term.at n=9A165770
• Champernowne primes.at n=0A176942