A068575 Numbers n such that, as strings, n is a substring of prime(n).

7, 6455, 6456, 6457, 6459, 6460, 6466, 9551, 303027, 440999, 968819, 5517973, 27737957, 93230839, 96664044, 46492090901

Offset

1,1

Comments

pi(2*10^12) < a(17) <= 426836115943. a(18) <= 732382677641. a(19) <= 4895576080181. [From Donovan Johnson, May 08 2010]

Links

Table of n, a(n) for n=1..16.

Example

Treated as strings, 6455 is a substring of 64553 = Prime(6455), so 6455 belongs to the sequence.
Pairs {n, prime(n)}: {7, 17}, {6455, 64553}, {6456, 64567}, {6457, 64577}, {6459, 64591}, {6460, 64601}, {6466, 64661}, {9551, 99551}, {303027, 4303027}, {440999, 6440999}, {968819, 14968819}, {5517973, 95517973}.

Mathematica

Select[Range[10^6], StringPosition[ToString[Prime[ # ]], ToString[ # ]] != {} &]
Select[Range[97*10^4], SequenceCount[IntegerDigits[Prime[#]], IntegerDigits[#]]>0&] (* The program generates the first 11 terms of the sequence. *) (* Harvey P. Dale, Nov 14 2022 *)

Crossrefs

Cf. A067248, A046883, A075902.

Sequence in context: A225067 A281358 A343145 * A158400 A221628 A220879

Adjacent sequences: A068572 A068573 A068574 * A068576 A068577 A068578

Keyword

base,nonn

Author

Joseph L. Pe, Mar 26 2002

Extensions

More terms from Zak Seidov, Sep 27 2002

Three more terms from Farideh Firoozbakht, Jan 06 2007

a(16) from Donovan Johnson, May 08 2010

Status

approved