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A265731
Powers C^z = A^x + B^y with all positive integers and x,y,z > 1, without multiplicity.
2
8, 9, 16, 25, 32, 36, 64, 81, 100, 125, 128, 144, 169, 196, 225, 243, 256, 289, 324, 343, 400, 441, 512, 576, 625, 676, 784, 841, 900, 1000, 1024, 1089, 1156, 1225, 1296, 1369, 1521, 1600, 1681, 1728, 1764, 1849, 2025, 2048, 2197, 2304, 2500, 2601, 2704, 2744, 2809, 2916, 3025, 3125
OFFSET
1,1
COMMENTS
This type of equation is used in the Fermat-Catalan conjecture, the ABC conjecture, etc., of course, with additional restrictions and conditions.
EXAMPLE
8 = 2^3 = 2^2 + 2^2; 9 = 3^2 = 1^3 + 2^3; 16 = 4^2 = 2^3 + 2^3; etc.
PROG
(PARI) A265731(lim, bflag=0)={my(Lcz=List(1), Lb=List(), czn, lczn, lbn, lim2=logint(lim, 2), lim3);
for(z=2, lim2, lim3=sqrtnint(lim, z); for(C=2, lim3, listput(Lcz, C^z)));
Lcz=Set(Lcz); lczn = #Lcz; if(lczn==0, return(-1));
for(i=1, lczn, for(j=i, lczn, czn=Lcz[i]+Lcz[j]; if(czn>lim, break);
if(setsearch(Lcz, czn), listput(Lb, czn)))); listsort(Lb, 1); lbn=#Lb;
if(bflag, for(i=1, lbn, print(i , " ", Lb[i]))); if(!bflag, return(Vec(Lb))); }
\\ Anatoly E. Voevudko, Nov 23 2015
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Anatoly E. Voevudko, Dec 14 2015
STATUS
approved