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%I #24 Mar 17 2020 12:03:02
%S 9,4,9,16,9,16,9,16,25,16,25,16,25,16,25,36,25,36,25,36,25,36,25,36,
%T 49,36,49,36,49,36,49,36,49,36,49,64,49,64,49,64,49,64,49,64,49,64,49,
%U 64,81,64,81,64,81,64,81,64,81,64,81,64,81,64,81,100,81,100,81,100,81,100,81,100,81,100,81,100,81,100,81,100
%N The least square larger than n with same parity as n.
%F a(n) = A256244(n)^2 = n + 2*A256243(n)).
%e 9 is the least odd square > 1;
%e 4 is the least even square > 2;
%e 9 is the least odd square > 3.
%t f[n_] := Block[{s = If[n == 1, Range[3]^2, Range[2 Ceiling@ Sqrt@ n]^2]}, If[EvenQ@ n, SelectFirst[s, EvenQ@ # && # > n &], SelectFirst[s, OddQ@ # && # > n &]]]; Array[f, 120] (* _Michael De Vlieger_, Mar 25 2015 *)
%o (Sage)
%o A = []
%o for i in [1..100]:
%o for y in [1..100]:
%o x = y**2
%o if x>i and (x-i)%2==0:
%o A.append(x)
%o break
%o A
%Y Cf. A256243, A256244.
%K nonn,easy
%O 1,1
%A _Tom Edgar_ and _Zak Seidov_, Mar 25 2015
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