The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons Foundation.

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A061911 Square root of the sum of the digits of k^2 when this sum is a square. 2
 1, 2, 3, 3, 3, 1, 2, 3, 4, 4, 3, 3, 2, 3, 4, 4, 3, 4, 3, 4, 3, 3, 3, 4, 4, 3, 5, 4, 5, 5, 4, 5, 3, 5, 4, 1, 2, 3, 4, 4, 3, 2, 3, 4, 5, 3, 4, 5, 4, 4, 4, 4, 4, 3, 5, 5, 5, 4, 5, 3, 5, 4, 5, 5, 2, 3, 4, 4, 3, 4, 5, 4, 5, 4, 4, 5, 4, 4, 4, 3, 5, 5, 6, 4, 5, 5, 5, 5, 5, 5, 3, 4, 4, 4, 5, 3, 4, 3, 5, 4, 5, 4, 5, 4, 3 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 LINKS FORMULA a(n) = sqrt(A004159(A061910(n))) = sqrt(A007953((A061910(n))^2)). - Zak Seidov, Jul 04 2012 EXAMPLE 6^2 = 36 and 3+6 = 9 is a square, thus 3 is in the sequence. 13^2 = 169 and 1+6+9 = 16 is a square, thus 4 is in the sequence. MAPLE readlib(issqr): f := []: for n from 1 to 200 do if issqr(convert(convert(n^2, base, 10), `+`)) then f := [op(f), sqrt(convert(convert(n^2, base, 10), `+`))] fi; od; f; MATHEMATICA Select[Table[Sqrt[Total[IntegerDigits[n^2]]], {n, 350}], IntegerQ] (* Jayanta Basu, May 06 2013 *) CROSSREFS Cf. A007953, A004159, A061909, A061910, A061912. Sequence in context: A308100 A171576 A016738 * A328397 A082239 A207814 Adjacent sequences:  A061908 A061909 A061910 * A061912 A061913 A061914 KEYWORD nonn,base AUTHOR Asher Auel (asher.auel(AT)reed.edu), May 17 2001 STATUS approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

Last modified September 21 07:28 EDT 2021. Contains 347596 sequences. (Running on oeis4.)