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A046030 Numbers whose digits are squares. 9
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 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,3
LINKS
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
KEYWORD
nonn,base
AUTHOR
EXTENSIONS
Offset corrected by Amiram Eldar, Feb 15 2024
STATUS
approved

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Last modified March 29 11:14 EDT 2024. Contains 371278 sequences. (Running on oeis4.)