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Numbers obtained by concatenating the squares of the digits of prime(n).
2

%I #24 Sep 08 2022 08:46:08

%S 4,9,25,49,11,19,149,181,49,481,91,949,161,169,1649,259,2581,361,3649,

%T 491,499,4981,649,6481,8149,101,109,1049,1081,119,1449,191,1949,1981,

%U 11681,1251,12549,1369,13649,1499,14981,1641,1811,1819,18149,18181,411,449

%N Numbers obtained by concatenating the squares of the digits of prime(n).

%H Harvey P. Dale, <a href="/A244557/b244557.txt">Table of n, a(n) for n = 1..1000</a>

%F a(n) = A048385(A000040(n)).

%e For n = 7, prime(7) = 17 and a(7) = 149, which is the concatenation of the squares of the digits of 17. For n = 31, prime(31) = 127 and a(31) = 1449; but this term also appears at index 200, in fact prime(200) = 1223 and a(200) = 1449.

%t Table[FromDigits[Flatten[IntegerDigits/@(IntegerDigits[Prime[n]]^2)]],{n,50}] (* _Harvey P. Dale_, Aug 18 2016 *)

%o (Magma) [StringToInteger(&cat[IntegerToString(h): h in Reverse([i^2: i in Intseq(p)])]): p in PrimesUpTo(250)];

%Y Cf. A000040, A048385.

%K nonn,base

%O 1,1

%A _Vincenzo Librandi_, Jul 02 2014

%E Edited by _Bruno Berselli_, Jul 02 2014