A053918 Numbers k such that k^2 contains only digits {2,3,5}.

5, 15, 235, 485, 1885, 5765, 15885, 50235, 57665, 72335, 1798765, 15249765, 187703365, 179876492415, 159789024443333515, 576387476638096486959455635

Offset: 1

Author

Patrick De Geest, Mar 15 2000

Keywords

• nonn
• base
• more

Links

• Michael S. Branicky, Python program
• Patrick De Geest, Squares containing at most three distinct digits, Index entries for related sequences
• Author?, Source(txt)
• H. Mishima Squares consisted of 3 different digits

Crossrefs

Cf. A053919.

Programs

Python

# see link for faster version
def aupto(limit):
  alst = []
  for k in range(1, limit+1):
    if set(str(k*k)) <= set("235"): alst.append(k)
  return alst
print(aupto(2*10**6)) # Michael S. Branicky, May 15 2021

Extensions

More terms from C. Ronaldo (aga_new_ac(AT)hotmail.com), Jan 03 2005

One more term from Mishima's webpage added by Max Alekseyev, Jun 17 2011

a(16) from Zhao Hui Du, Feb 29 2024