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A239587
Cubes that are cyclops numbers.
6
0, 74088, 1520875, 1560896, 1860867, 2460375, 4330747, 4410944, 7880599, 123505992, 144703125, 172808693, 177504328, 179406144, 191102976, 194104539, 211708736, 232608375, 241804367, 264609288, 288804781, 295408296, 335702375, 338608873, 368601813, 374805361
OFFSET
1,2
COMMENTS
Intersection of A000578 (Cubes) and A134808 (Cyclops numbers).
LINKS
FORMULA
a(n) = A239590(n)^3.
MATHEMATICA
cyclpsQ[n_]:=With[{len=IntegerLength[n]}, OddQ[len]&&DigitCount[n, 10, 0]==1&&IntegerDigits[n][[(len+1)/2]]==0]; Join[{0}, Select[ Range[ 800]^3, cyclpsQ]] (* Harvey P. Dale, Nov 05 2024 *)
PROG
(PARI)
is_cyclops(k) = {
if(k==0, return(1));
my(d=digits(k), j);
if(#d%2==0 || d[#d\2+1]!=0, return(0));
for(j=1, #d\2, if(d[j]==0, return(0)));
for(j=#d\2+2, #d, if(d[j]==0, return(0)));
return(1)}
s=[]; for(n=0, 2000, if(is_cyclops(n^3), s=concat(s, n^3))); s
KEYWORD
nonn,base,changed
AUTHOR
Colin Barker, Mar 24 2014
STATUS
approved