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 A206528 5^n concatenated with itself. 2

%I

%S 11,55,2525,125125,625625,31253125,1562515625,7812578125,390625390625,

%T 19531251953125,97656259765625,4882812548828125,244140625244140625,

%U 12207031251220703125,61035156256103515625,3051757812530517578125,152587890625152587890625

%N 5^n concatenated with itself.

%H Vincenzo Librandi, <a href="/A206528/b206528.txt">Table of n, a(n) for n = 0..200</a>

%F a(n) = A020338(5^n).

%e a(1)=55 because 5^1 concatenated with 5^1 is 55.

%t Table[FromDigits[Join[IntegerDigits[5^n],IntegerDigits[5^n]]],{n,0,20}]

%o (MAGMA) [Seqint(Intseq(5^n) cat Intseq(5^n)): n in [0..20]];

%Y Cf. A000351, A178664, A206527.

%K nonn,base,easy

%O 0,1

%A _Vincenzo Librandi_, Mar 17 2012

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Last modified September 28 06:17 EDT 2021. Contains 347703 sequences. (Running on oeis4.)