A227950 Number of decimal digits in the increasing sequence of primes obtainable by concatenating successive decrements from some power of 10.

3, 5, 5, 7, 9, 11, 13, 13, 15, 17, 19, 21, 25, 27, 53, 81, 85, 183, 191, 307, 377, 409, 475, 541, 565, 885, 1065, 1399, 1489, 2653, 4523, 4565, 5773, 7777, 14281

Offset

1,1

Links

Table of n, a(n) for n=1..35.

Example

1000999998997 is one of the primes described and provides a value of 13 in this sequence, with 1000000999999 providing the other (A227949(7) and A227949(8), in opposite order for the purposes of the FORMULA at that sequence (technically)).

Crossrefs

Cf. A227949, A227951.

Sequence in context: A219844 A168056 A122800 * A378356 A063202 A058020

Adjacent sequences: A227947 A227948 A227949 * A227951 A227952 A227953

Keyword

nonn,base,more

Author

James G. Merickel, Aug 22 2013

Status

approved