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A153139 Numbers n with property that n^2 is a concatenation of three 3-digit primes. 1

%I

%S 10171,10371,10447,10449,10451,11303,11801,11827,12319,12553,13387,

%T 13829,13847,13903,13913,14141,14549,15087,15097,15153,15847,16431,

%U 16841,16847,17549,18363,18379,18637,18697,18701,19319,19337,19579

%N Numbers n with property that n^2 is a concatenation of three 3-digit primes.

%C There are exactly 60 such numbers.

%H Harvey P. Dale, <a href="/A153139/b153139.txt">Table of n, a(n) for n = 1..60</a>

%e a(1)= 10171, 10171^2=103_449_241

%e a(2)= 10371, 10371^2=107_557_641

%e a(60)=31591, 31591^2=997_991_281

%t ttdpQ[n_]:=Module[{c=FromDigits/@Partition[IntegerDigits[n^2],3]}, Min[ IntegerLength[ c]] ==3&&AllTrue[c,PrimeQ]]; Select[Range[ 10000,31622], ttdpQ] (* Requires Mathematica version 10 or later *) (* _Harvey P. Dale_, Aug 26 2016 *)

%Y Cf. A153048, A153050

%K base,fini,nonn

%O 1,1

%A _Zak Seidov_, Dec 19 2008

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Last modified May 8 22:05 EDT 2021. Contains 343668 sequences. (Running on oeis4.)