A248126 - OEIS

%I #44 Dec 02 2023 16:37:30

%S 11,44,99,1166,2255,3366,4499,6644,8811,110000,112211,114444,116699,

%T 119966,222255,225566,228899,332244,336611,440000,444411,448844,

%U 552299,557766,662255,667766,772299,778844,884411,990000,996611,11002244,11008899,11115566

%N a(n) = n^2 with each digit repeated.

%C Inspired by A116699.

%H Michael De Vlieger, <a href="/A248126/b248126.txt">Table of n, a(n) for n = 1..10000</a>

%e 13^2 = 169, so a(13) = 116699.

%t a248126[n_Integer] :=

%t Module[{m}, m := IntegerDigits[n^2];

%t   FromDigits[Flatten[Transpose[List[m, m]]]]]; a248126 /@ Range[34] (* _Michael De Vlieger_, Nov 06 2014 *)

%t Table[FromDigits[Riffle[id=IntegerDigits[n^2],id]],{n,40}] (* _Harvey P. Dale_, Dec 19 2015 *)

%o (JavaScript)

%o for (i=1;i<40;i++) {

%o s=(i*i).toString();

%o for (j=0;j<s.length;j++) document.write(s.charAt(j)+s.charAt(j));

%o document.write(", ");

%o }

%o (PARI) a(n)= my(d = 11*digits(n^2)); fromdigits(d, 100) \\ _David A. Corneth_, Dec 02 2023

%o (Python)

%o def a(n): return int("".join(d*2 for d in str(n**2)))

%o print([a(n) for n in range(1, 35)]) # _Michael S. Branicky_, Dec 02 2023

%Y Cf. A020338, A044836.

%Y Cf. A116699, A338754.

%K nonn,easy,base

%O 1,1

%A _Jon Perry_, Nov 01 2014