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A239211 Squares that are not divisible by any of their nonzero digits. 4
49, 289, 529, 676, 2209, 2809, 4489, 5329, 5776, 5929, 6889, 7396, 8836, 9409, 20449, 24649, 26569, 27889, 29929, 30976, 34969, 37249, 37636, 38809, 49729, 54289, 55696, 59536, 64009, 65536, 66049, 67600, 75076, 76729, 80089, 82369, 85849, 94249, 97969 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
COMMENTS
Intersection of A000290 and A038772.
The sequence is infinite since it contains all the terms (5*10^k+3)^2, k>0. - Giovanni Resta, Mar 12 2014
LINKS
EXAMPLE
2809 is in the sequence because 2809 is not divisible by 2, 8 or 9.
MATHEMATICA
Select[Range[350]^2, NoneTrue[#/(IntegerDigits[#]/.(0->Nothing)), IntegerQ]&] (* Requires Mathematica version 10 or later *) (* Harvey P. Dale, Oct 08 2017 *)
PROG
(PARI) isOK(n) = my(v=vecsort(digits(n^2), , 8)); for(i=1+(v[1]==0), #v, if(n^2%v[i]==0, return(0))); 1
s=[]; for(n=1, 1000, if(isOK(n), s=concat(s, n^2))); s
CROSSREFS
Sequence in context: A158248 A219030 A167719 * A198437 A144407 A089552
KEYWORD
nonn,base
AUTHOR
Colin Barker, Mar 12 2014
STATUS
approved

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Last modified June 16 07:19 EDT 2024. Contains 373423 sequences. (Running on oeis4.)