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.
isok(n) = length(setintersect(Set(digits(n^2)), Set(digits((n+1)^2)))) == 0; \\ Michel Marcus, Oct 15 2013
a(0)=1 because squares 0^2=0 and (0+1)^2=1 have no common digits, a(9)=6 because squares 9^2=81 and (9+6)^2=225 have no common digits.
lpk[n_]:=Module[{k=1},While[ContainsAny[IntegerDigits[n^2], IntegerDigits[ (n+k)^2]], k++];k]Array[lpk,100,0] (* Harvey P. Dale, Jun 17 2016 *)
k=4 is a term: the consecutive primes are 251 and 257. In base 4 their representations are 3323 and 10001, which have no common digit.
Select[Range[100], ! IntersectingQ @@ IntegerDigits[NextPrime[4^#, {-1, 1}], 4] &] (* Amiram Eldar, Mar 03 2023 *)
isok(k) = #setintersect(Set(digits(precprime(4^k), 4)), Set(digits(nextprime(4^k), 4))) == 0; \\ Michel Marcus, Mar 03 2023
from sympy.ntheory import digits, nextprime, prevprime
def ok(n):
p, q = prevprime(4**n), nextprime(4**n)
return set(digits(p, 4)[1:]) & set(digits(q, 4)[1:]) == set()
print([k for k in range(1, 99) if ok(k)]) # Michael S. Branicky, Mar 03 2023
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