A037023 Triangle in which row n lists the first n digits of sqrt(n) (rounded).

1, 1, 4, 1, 7, 3, 2, 0, 0, 0, 2, 2, 3, 6, 1, 2, 4, 4, 9, 4, 9, 2, 6, 4, 5, 7, 5, 1, 2, 8, 2, 8, 4, 2, 7, 1, 3, 0, 0, 0, 0, 0, 0, 0, 0, 3, 1, 6, 2, 2, 7, 7, 6, 6, 0, 3, 3, 1, 6, 6, 2, 4, 7, 9, 0, 4, 3, 4, 6, 4, 1, 0, 1, 6, 1, 5, 1, 4, 3, 6, 0, 5, 5, 5, 1, 2, 7, 5, 4, 6, 4, 3, 7, 4, 1, 6, 5, 7, 3

Offset

1,3

Links

T. D. Noe, Rows n = 1..100 of triangle, flattened

Example

Triangle begins:
  1;
  1, 4;
  1, 7, 3;
  2, 0, 0, 0;
  2, 2, 3, 6, 1;
  2, 4, 4, 9, 4, 9;
  2, 6, 4, 5, 7, 5, 1;
  2, 8, 2, 8, 4, 2, 7, 1;
  3, 0, 0, 0, 0, 0, 0, 0, 0;
  3, 1, 6, 2, 2, 7, 7, 6, 6, 0;
  3, 3, 1, 6, 6, 2, 4, 7, 9, 0, 4;
  3, 4, 6, 4, 1, 0, 1, 6, 1, 5, 1, 4;
  3, 6, 0, 5, 5, 5, 1, 2, 7, 5, 4, 6, 4;
  ...

Mathematica

sds[n_]:=Module[{c=RealDigits[Sqrt[n], 10, n+1][[1]]}, If[Last[c]<5, Most[c], IntegerDigits[ FromDigits[Most[c]]+1]]]; Flatten[Array[sds, 20]] (* Harvey P. Dale, Dec 13 2011 *)

Crossrefs

Cf. A037022.

Sequence in context: A158860 A335619 A037022 * A143971 A367898 A016688

Adjacent sequences: A037020 A037021 A037022 * A037024 A037025 A037026

Keyword

nonn,base,nice,easy,tabl

Author

Jonas Persson (jptmp(AT)hotmail.com), N. J. A. Sloane

Status

approved