A248126 a(n) = n^2 with each digit repeated.

11, 44, 99, 1166, 2255, 3366, 4499, 6644, 8811, 110000, 112211, 114444, 116699, 119966, 222255, 225566, 228899, 332244, 336611, 440000, 444411, 448844, 552299, 557766, 662255, 667766, 772299, 778844, 884411, 990000, 996611, 11002244, 11008899, 11115566

Offset

1,1

Comments

Inspired by A116699.

Links

Michael De Vlieger, Table of n, a(n) for n = 1..10000

Example

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

Mathematica

a248126[n_Integer] :=
Module[{m}, m := IntegerDigits[n^2];
  FromDigits[Flatten[Transpose[List[m, m]]]]]; a248126 /@ Range[34] (* Michael De Vlieger, Nov 06 2014 *)
Table[FromDigits[Riffle[id=IntegerDigits[n^2], id]], {n, 40}] (* Harvey P. Dale, Dec 19 2015 *)

Prog

(JavaScript)
for (i=1; i<40; i++) {
s=(i*i).toString();
for (j=0; j<s.length; j++) document.write(s.charAt(j)+s.charAt(j));
document.write(", ");
}
(PARI) a(n)= my(d = 11*digits(n^2)); fromdigits(d, 100) \\ David A. Corneth, Dec 02 2023
(Python)
def a(n): return int("".join(d*2 for d in str(n**2)))
print([a(n) for n in range(1, 35)]) # Michael S. Branicky, Dec 02 2023

Crossrefs

Cf. A020338, A044836.

Cf. A116699, A338754.

Sequence in context: A061976 A070930 A033584 * A253445 A172526 A111080

Adjacent sequences: A248123 A248124 A248125 * A248127 A248128 A248129

Keyword

nonn,easy,base

Author

Jon Perry, Nov 01 2014

Status

approved