cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A030289 a(n+1) is the next larger cube with no digits in common with a(n), a(0) = 0.

Original entry on oeis.org

0, 1, 8, 27, 64, 125, 343, 512, 4096, 5832, 64000, 91125, 300763, 941192, 3375000, 8489664, 13312053, 86444696669696, 100175333300307, 488224224494488, 510657175657000, 2233398984434344, 5177717000000000, 6393843393228864
Offset: 0

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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

Crossrefs

Squares whose digits do not appear in previous term: A030288.
Primes whose digits do not appear in previous term: A030284.
Cf. A030290: cube roots of the terms.

Programs

  • 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 *)
  • 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

Formula

a(n) = A030290(n)^3. - David W. Wilson, Nov 08 2017