A101809 Sequence formed by writing out the primes, one digit at a time, prefixing each prime by the number of digits it contains (the latter number being written as a normal decimal number, not digit-by-digit).

1, 2, 1, 3, 1, 5, 1, 7, 2, 1, 1, 2, 1, 3, 2, 1, 7, 2, 1, 9, 2, 2, 3, 2, 2, 9, 2, 3, 1, 2, 3, 7, 2, 4, 1, 2, 4, 3, 2, 4, 7, 2, 5, 3, 2, 5, 9, 2, 6, 1, 2, 6, 7, 2, 7, 1, 2, 7, 3, 2, 7, 9, 2, 8, 3, 2, 8, 9, 2, 9, 7, 3, 1, 0, 1, 3, 1, 0, 3, 3, 1, 0, 7, 3, 1, 0, 9, 3, 1, 1, 3, 3, 1, 2, 7, 3, 1, 3, 1, 3, 1, 3, 7, 3

Offset

1,2

Comments

List of pairs: (number of digits of prime(n), digits of prime(n)).

As a decimal number this is 0.12131517211213217219223....

Links

Table of n, a(n) for n=1..104.

Mathematica

Flatten[{IntegerLength[#], IntegerDigits[#]}&/@Prime[Range[50]]] (* Harvey P. Dale, Jul 12 2011 *)

Crossrefs

Sequence in context: A217668 A119479 A130008 * A127203 A227288 A336752

Adjacent sequences: A101806 A101807 A101808 * A101810 A101811 A101812

Keyword

nonn,base

Author

Ryan B. Florence (rflorence2004(AT)yahoo.com), Feb 01 2005

Status

approved