cp's OEIS Frontend

A247883 Consecutive exclusionary cubes: Digits of n are not present in n^3 and digits of n+1 are not present in (n+1)^3.

%I A247883 #13 Mar 11 2025 04:06:23
%S A247883 2,7,47,52,187,222,477,587,5522,6777
%N A247883 Consecutive exclusionary cubes: Digits of n are not present in n^3 and digits of n+1 are not present in (n+1)^3.
%C A247883 If it exists, a(11) > 10^7.
%C A247883 All terms == 2 (mod 5). - _Robert Israel_, Mar 10 2025
%p A247883 filter:= proc(n) convert(convert(n,base,10),set) intersect convert(convert(n^3,base,10),set) = {} end proc:
%p A247883 select(t -> filter(t) and filter(t+1), [seq(i,i=2..10^6, 5)]); # _Robert Israel_, Mar 10 2025
%o A247883 (Python)
%o A247883 for n in range(10**6):
%o A247883   s, t = str(n), str(n+1)
%o A247883   s3, t3 = str(n**3), str((n+1)**3)
%o A247883   c = 0
%o A247883   for i in s:
%o A247883     if s3.count(i):
%o A247883       c += 1
%o A247883       break
%o A247883   for j in t:
%o A247883     if t3.count(j):
%o A247883       c += 1
%o A247883       break
%o A247883   if not c:
%o A247883     print(n, end=', ')
%o A247883 (PARI)
%o A247883 for(n=1,10^6,s=digits(n);t=digits(n+1);s3=digits(n^3);t3=digits((n+1)^3);if(#vecsort(concat(s,s3),,8)==#vecsort(s,,8)+#vecsort(s3,,8)&&#vecsort(concat(t,t3),,8)==#vecsort(t,,8)+#vecsort(t3,,8),print1(n,", ")))
%Y A247883 Cf. A029785.
%K A247883 nonn,base,more
%O A247883 1,1
%A A247883 _Derek Orr_, Sep 25 2014
%E A247883 Definition corrected by _Robert Israel_, Mar 10 2025