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A084009 a(n) = n^2 concatenated with reverse(n^2) divided by 11. 1

%I

%S 0,1,4,9,151,232,333,454,586,738,9091,11011,13131,15451,17881,20502,

%T 23332,26362,29493,32833,36364,40104,44044,48175,52425,56866,61516,

%U 66357,71317,76468,81819,87379,931291,990891,1051501,1114111,1178811

%N a(n) = n^2 concatenated with reverse(n^2) divided by 11.

%e a(12) = 144441/11 = 13131.

%p a:=proc(n) local nn,s: nn:=convert(n^2,base,10): s:=nops(nn): (10^s*n^2+add(nn[1+s-j]*10^(j-1),j=1..s))/11 end: seq(a(n),n=0..39); # _Emeric Deutsch_, Feb 25 2005

%t n2c[n_]:=Module[{idn2=IntegerDigits[n^2]},FromDigits[Join[idn2, Reverse[ idn2]]]/11]; Array[n2c,40,0] (* _Harvey P. Dale_, May 27 2014 *)

%o (PARI) a(n) = my(d=digits(n^2)); eval(fromdigits(concat(d, Vecrev(d))))/11; \\ _Michel Marcus_, Sep 12 2017

%Y Cf. A084008, A084010.

%K base,nonn

%O 0,3

%A _Amarnath Murthy_ and Meenakshi Srikanth (menakan_s(AT)yahoo.com), May 23 2003

%E More terms from _Emeric Deutsch_, Feb 25 2005

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Last modified January 17 06:10 EST 2022. Contains 350378 sequences. (Running on oeis4.)