OFFSET
0,3
COMMENTS
From a(24) on, even-indexed terms are powers of 1000, odd-indexed terms are the next larger cube to a(n-1)*20/9 with no digit 0 or 1, cf. A030290. - M. F. Hasler, Nov 12 2017
LINKS
David W. Wilson, Table of n, a(n) for n = 0..90
FORMULA
a(n) = A030290(n)^3. - David W. Wilson, Nov 08 2017
MATHEMATICA
bb={0}; idi1=IntegerDigits[0]; Do[idi=IntegerDigits[r=i^3]; If[Intersection[idi, idi1]=={}, bb={bb, r}; idi1=idi], {i, 1, 100000}]; fla=Flatten[bb] (* Zak Seidov, Feb 17 2005 *)
Nest[Append[#, Block[{k = Last@ # + 1, m = IntegerDigits[Last[#]^3]}, While[IntersectingQ[IntegerDigits[k^3], m], k++]; k]] &, {0}, 23]^3 (* Michael De Vlieger, Nov 13 2017 *)
PROG
(PARI) next_A030289(n, D(n)=Set(digits(n)), S=D(n))={if(n>6e15, S[1]&&return(1000^(logint(n, 1000)+1)); n=n*20\9); for(k=sqrtnint(n, 3)+1, oo, #setintersect(D(k^3), S)||return(k^3))} \\ M. F. Hasler, Nov 12 2017
CROSSREFS
KEYWORD
nonn,base
AUTHOR
STATUS
approved