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A249898 a(n+1) is next smallest square not divisible by 10 beginning with a(n), initial term is 8.

%I A249898 #17 Mar 07 2025 16:13:24
%S A249898 8,81,81225,8122515625,812251562541751472569,
%T A249898 812251562541751472569881528811450814530084
%N A249898 a(n+1) is next smallest square not divisible by 10 beginning with a(n), initial term is 8.
%H A249898 Hiroaki Yamanouchi, <a href="/A249898/b249898.txt">Table of n, a(n) for n = 1..10</a>
%o A249898 (PARI) a(n)=k=n; s=1; while(s<5*10^7, if(s%10, if(s^2\(10^(#Str(s^2)-#Str(k)))==k, print1(s^2, ", "); k=s^2)); s++)
%o A249898 a(8)
%o A249898 (Python)
%o A249898 def f(x):
%o A249898   print(x, end=', ')
%o A249898   n = x
%o A249898   s = 1
%o A249898   while s < 10**7:
%o A249898     if s % 10:
%o A249898       S = str(s**2)
%o A249898       if S.startswith(str(n)):
%o A249898         print(s**2, end=', ')
%o A249898         n = s**2
%o A249898     s += 1
%o A249898 f(8)
%Y A249898 Cf. A048559, A048561.
%K A249898 nonn,base
%O A249898 1,1
%A A249898 _Derek Orr_, Nov 08 2014