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%I #29 Oct 12 2019 21:32:04
%S 88,332,334,335,336,337,338,339,664,665,667,668,669,880,881,882,883,
%T 995,996,997,998,3317,3318,3319,3320,3321,3322,3323,3324,3325,3326,
%U 3327,3328,3329,3332,3334,3335,3336,3337,3338,3339,3340,3341,3342,3343,3344,3345,3346,3347
%N Numbers k such that k^2 starts with at least the same number >= 2 of equal digits as does k itself.
%H Reiner Moewald, <a href="/A323612/b323612.txt">Table of n, a(n) for n = 1..24527</a>
%e 332^2 = 110224, i.e., both the integer and its square start with two equal digits.
%e Also 334^2 = 111556, so 334 is a term.
%o (Python)
%o def zahl(z):
%o a = str(z)
%o r = 0
%o while r < len(a) and a[0] == a[r]:
%o r = r + 1
%o b = str(z*z)
%o s = 0
%o while r < len(b) and b[0] == b[s]:
%o s = s + 1
%o if r >= 2:
%o return(s-r)
%o else:
%o return(-1)
%o anz = 0
%o for i in range(1000000):
%o if zahl(i) >= 0:
%o anz = anz +1
%o print(anz, i)
%o (PARI) nbi(d) = my(nb=1); for(k=2, #d, if (d[k] == d[1], nb++, break)); nb;
%o isok(n) = my(nb = nbi(digits(n))); (nb > 1) && (nbi(digits(n^2)) >= nb); \\ _Michel Marcus_, Apr 24 2019
%K nonn,base
%O 1,1
%A _Reiner Moewald_, Jan 20 2019
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