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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
OFFSET
1,1
COMMENTS
There are exactly 60 such numbers.
LINKS
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
KEYWORD
base,fini,nonn
AUTHOR
Zak Seidov, Dec 19 2008
STATUS
approved