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A249895 a(n+1) is next smallest square not divisible by 10 beginning with a(n), initial term is 5.

%I A249895 #15 May 22 2025 10:21:41
%S A249895 5,529,529984,52998485796,5299848579629072273476,
%T A249895 529984857962907227347600150092608188876380736
%N A249895 a(n+1) is next smallest square not divisible by 10 beginning with a(n), initial term is 5.
%H A249895 Hiroaki Yamanouchi, <a href="/A249895/b249895.txt">Table of n, a(n) for n = 1..10</a>
%o A249895 (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 A249895 a(5)
%o A249895 (Python)
%o A249895 def f(x):
%o A249895   print(x, end=', ')
%o A249895   n = x
%o A249895   s = 1
%o A249895   while s < 10**7:
%o A249895     if s % 10:
%o A249895       S = str(s**2)
%o A249895       if S.startswith(str(n)):
%o A249895         print(s**2, end=', ')
%o A249895         n = s**2
%o A249895     s += 1
%o A249895 f(5)
%Y A249895 Cf. A048559, A048561.
%K A249895 nonn,base
%O A249895 1,1
%A A249895 _Derek Orr_, Nov 08 2014