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%I #15 Mar 18 2022 00:02:03
%S 1,2,2,3,4,4,4,4,4,4,4,4,4,4,4,5,6,6,6,6,6,6,6,6,7,8,8,8,8,8,8,8,8,8,
%T 8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,
%U 8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8
%N a(1)=1; for n > 1, a(n) = a(floor(sqrt(n))) + a(floor(sqrt(n-1))).
%e a(1) = 1,
%e a(2) = a(1) + a(1) = 2,
%e a(3) = a(1) + a(1) = 2,
%e a(4) = a(2) + a(1) = 3,
%e a(5) = a(2) + a(2) = 4,
%e a(6) = a(2) + a(2) = 4,
%e a(7) = a(2) + a(2) = 4,
%e a(8) = a(2) + a(2) = 4,
%e a(9) = a(3) + a(2) = 4,
%e a(10) = a(3) + a(3) = 4,
%e a(11) = a(3) + a(3) = 4, etc.
%o (PARI) a(n) = if (n==1, 1, my(r=sqrtint(n), s=sqrtint(n-1)); a(r) + a(s)); \\ _Michel Marcus_, Mar 17 2022
%Y Cf. A000196.
%K easy,nonn
%O 1,2
%A _Ctibor O. Zizka_, Mar 06 2010
%E More terms from _Michel Marcus_, Mar 17 2022
%E Name simplified by _Jon E. Schoenfield_, Mar 17 2022
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