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%I #19 Jul 10 2015 20:12:14
%S 0,0,0,1,3,4,8,21,55,72,144,377,987,1292,2584,6765,17711,23184,46368,
%T 121393,317811,416020,832040,2178309,5702887,7465176
%N Square root of floor(A055812(n) / 5).
%C Or: Numbers whose square yields another square when written in base 5.
%C (For the first 3 terms, the above "base 5" interpretation is questionable, since they have only 1 digit in base 5. It is understood that dropping this digit yields 0.)
%C Base-5 analog of A031150 [base 10], A001353 [base 3], A001542 [base 2].
%C The square roots of A055812 are listed in A204520.
%F Empirical g.f.: x^4*(x^5+3*x^4+8*x^3+4*x^2+3*x+1) / ((x^4-4*x^2-1)*(x^4+4*x^2-1)). - _Colin Barker_, Sep 15 2014
%o (PARI) b=5;for(n=1,2e9,issquare(n^2\b) && print1(sqrtint(n^2\b),","))
%Y Cf. A055792, A055793, A204519, A204517, A204512, A204503 and A023110.
%K nonn
%O 1,5
%A _M. F. Hasler_, Jan 15 2012
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