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A378498
Squares where larger digits have smaller multiplicity.
2
1, 4, 9, 100, 121, 225, 400, 484, 676, 900, 10000, 11881, 40000, 44944, 69696, 90000, 111556, 202500, 220900, 225625, 232324, 261121, 265225, 300304, 442225, 444889, 695556, 1000000, 1002001, 1020100, 1210000, 2250000, 2295225, 4000000, 4008004, 4080400, 4840000, 5112121, 6760000, 8008900, 9000000
OFFSET
1,2
COMMENTS
Conjecture: a(n) ≍ n^2. - Charles R Greathouse IV, Nov 29 2024
LINKS
Charles R Greathouse IV, Table of n, a(n) for n = 1..10000
FORMULA
n^2 << a(n) << 1.001^n. - Charles R Greathouse IV, Nov 29 2024
MATHEMATICA
decreasingQ[L_]:=Max[Rest[(L-RotateRight[L])]]<0;
sortedQ[n_]:=decreasingQ[Sort[Tally[IntegerDigits[n]]][[All, 2]]];
Select[Range[10000]^2, sortedQ]
PROG
(PARI) has(n)=my(d=matreduce(digits(n))[, 2]); for(i=2, #d, if(d[i]>=d[i-1], return(0))); 1
list(lim)=my(v=List()); for(n=1, sqrtint(lim\1), if(has(n^2), listput(v, n^2))); Vec(v) \\ Charles R Greathouse IV, Nov 29 2024
CROSSREFS
KEYWORD
nonn,base
AUTHOR
Erich Friedman, Nov 28 2024
STATUS
approved