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A334161
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Least positive integer whose square root starts with just n odd decimal digits.
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1
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4, 1, 10, 3, 63, 129, 91, 1123, 249, 384, 3131, 391, 2823, 14293, 9996, 100603, 17260, 140863, 999960, 39984, 1837521, 11289570, 999996, 26336742, 3999840, 15999968, 29116075, 26824089, 366858085, 308642, 99999996, 314558578, 6399999872, 1599999968, 381808465
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OFFSET
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0,1
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COMMENTS
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We also have a(49) = 39999999984, a(54) = 3999999999840, a(59) = 3999999999984. - Giovanni Resta, Apr 18 2020
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LINKS
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EXAMPLE
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Square root of first terms: 2, 1.0, 3.16, 1.732, 7.9372, 11.3578, ...
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PROG
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(PARI) a(n) = {my(g=10^n, v); for(k=1, oo, v=digits(floor(sqrt(k)*g))[1..n+1]; if(v[n+1]%2==0 && setintersect([1, 3, 5, 7, 9], v=Set(v[1..n]))==v, return(k))); }
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CROSSREFS
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KEYWORD
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nonn,base
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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