A192608 - OEIS

%I #17 Jun 25 2022 17:21:30

%S 9,39,69,228,294,594,612,801,849,921,984,1821,1827,1842,1854,1872,

%T 1893,1896,2031,2193,2202,2319,2370,2421,2454,2466,2508,2535,2604,

%U 2607,2712,2997,3009,3084,3102,3108,3351,3477,3843,3879,3897,3900,3921,4095,4161

%N Numbers n such that the concatenation of n^5 n^4 n^3 n^2 n^1 n^0 is prime.

%H Giovanni Resta, <a href="/A192608/b192608.txt">Table of n, a(n) for n = 1..1000</a>

%e 9 is in the list because the concatenation of 9^5 9^4 9^3 9^2 9^1 9^0 is 5904965617298191 and this number is prime.

%t Select[Range[4200],PrimeQ[FromDigits[Flatten[IntegerDigits/@{#^5,#^4,#^3,#^2,#,1}]]]&] (* _Harvey P. Dale_, Jun 25 2022 *)

%o (PARI) isok(n) = {s = ""; for(i=0, 5, s = concat(Str(n^i), s)); isprime(eval(s));} \\ _Michel Marcus_, Feb 04 2014

%o (PARI) is(n)=isprime(eval(Str(n^5,n^4,n^3,n^2,n,1))) \\ _Charles R Greathouse IV_, Feb 04 2014

%Y Cf. A192609, A192610.

%K nonn,base

%O 1,1

%A _Claudio Meller_, Jul 05 2011

%E Extended by _Charles R Greathouse IV_, Jul 05 2011