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 A153139 Numbers n with property that n^2 is a concatenation of three 3-digit primes. 1
 10171, 10371, 10447, 10449, 10451, 11303, 11801, 11827, 12319, 12553, 13387, 13829, 13847, 13903, 13913, 14141, 14549, 15087, 15097, 15153, 15847, 16431, 16841, 16847, 17549, 18363, 18379, 18637, 18697, 18701, 19319, 19337, 19579 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS There are exactly 60 such numbers. LINKS Harvey P. Dale, Table of n, a(n) for n = 1..60 EXAMPLE a(1)= 10171, 10171^2=103_449_241 a(2)= 10371, 10371^2=107_557_641 a(60)=31591, 31591^2=997_991_281 MATHEMATICA 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 *) CROSSREFS Cf. A153048, A153050 Sequence in context: A172810 A231030 A323486 * A243974 A251274 A184205 Adjacent sequences: A153136 A153137 A153138 * A153140 A153141 A153142 KEYWORD base,fini,nonn AUTHOR Zak Seidov, Dec 19 2008 STATUS approved

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Last modified March 28 16:30 EDT 2023. Contains 361596 sequences. (Running on oeis4.)