A112013 Primes p such that there exists at least one number j and pi(p)= d_1 d_2 ... d_j*d_(j+1) d_(j+2) ... d_k where d_1 d_2 ...d_k is the decimal expansion of p.

17, 73, 619, 1117, 64591, 64601, 64661, 2077121, 5070613, 8883067, 2121104897, 4387047283, 14304478789, 503890508623, 1547037000637

Offset

1,1

Comments

This sequence is the prime subsequence of the sequence A112012. There is no further term up to prime(26000000).

Contribution from David Wasserman, Mar 26 2009: (Start)

In all terms after 64661, d_(j+1) = 0.

No more terms < prime(822900000) (End)

a(16) > 2*10^12. - Giovanni Resta, Feb 27 2013

Links

Table of n, a(n) for n=1..15.

Example

8883067 is in the sequence because 8883067 is prime;
pi(8883067)=595161 & 595161=8883*067. Note that for this term j=4.

Mathematica

Do[If[MemberQ[h=IntegerDigits[Prime[m]]; k=Length[h]; Table[FromDigits[Table[h[[i]], {i, j}]]*FromDigits[Table[h[[i]], {i, j+1, k}]], {j, k}], m], Print[m]], {m, 26000000}]

Crossrefs

Cf. A112012.

Sequence in context: A201262 A146658 A145440 * A165691 A154419 A208399

Adjacent sequences: A112010 A112011 A112012 * A112014 A112015 A112016

Keyword

base,more,nonn

Author

Farideh Firoozbakht, Oct 09 2005

Extensions

More terms from David Wasserman, Mar 26 2009

a(14)-a(15) from Giovanni Resta, Feb 27 2013

Status

approved