A046030 Numbers whose digits are squares.

0, 1, 4, 9, 10, 11, 14, 19, 40, 41, 44, 49, 90, 91, 94, 99, 100, 101, 104, 109, 110, 111, 114, 119, 140, 141, 144, 149, 190, 191, 194, 199, 400, 401, 404, 409, 410, 411, 414, 419, 440, 441, 444, 449, 490, 491, 494, 499, 900, 901, 904, 909, 910, 911, 914, 919

Offset

1,3

Links

Bruno Berselli, Table of n, a(n) for n = 1..1001

Robert Baillie and Thomas Schmelzer, Summing Kempner's Curious (Slowly-Convergent) Series, Mathematica Notebook kempnerSums.nb, Wolfram Library Archive, 2008.

Eric Weisstein's World of Mathematics, Smarandache Sequences.

Formula

Sum_{n>=2} 1/a(n) = 2.105050135115910443669713125834050962799269137280589957713644901011872709688... (calculated using Baillie and Schmelzer's kempnerSums.nb, see Links). - Amiram Eldar, Feb 15 2024

Mathematica

Union[FromDigits/@Flatten[With[{l={0, 1, 4, 9}}, Table[Tuples[l, {i}], {i, 3}]], 1]]  (* Harvey P. Dale, Dec 19 2010 *)
Select[Range[0, 999], Intersection[{2, 3, 5, 6, 7, 8}, Union[IntegerDigits[#]]] == {} &] (* T. D. Noe, Dec 20 2010 *)

Prog

(Magma) [n: n in [0..1000] | forall{d: d in Intseq(n) | d in [0, 1, 4, 9]}]; // Bruno Berselli, Jan 10 2013
(PARI) is(n)=#setintersect(Set(digits(n)), [2, 3, 5, 6, 7, 8])==0 \\ Charles R Greathouse IV, Feb 11 2017

Crossrefs

Sequence in context: A266297 A174800 A062371 * A125726 A352323 A175308

Adjacent sequences: A046027 A046028 A046029 * A046031 A046032 A046033

Keyword

nonn,base

Author

Eric W. Weisstein

Extensions

Offset corrected by Amiram Eldar, Feb 15 2024

Status

approved