%I A117580
%S A117580 1,9,25,27,49,81,125,169,225,343,361,441,729,729,841,1331,1369,1521,
%T A117580 2197,2025
%N A117580 a cubic quadratic sequence arranged so that the modulo 3 equals one cubic 
               sequence is just ahead of the quadratic sequence ( called here the 
               Maestro sequence).
%C A117580 Arranged so that they are near the Magic numbers ( nuclear shell filling 
               numbers): called Maestro as they have to be conducted like an orcestra 
               to get them to behave this way.
%F A117580 g[n_] := (n - Floor[n/3])^3 /; Mod[n, 3] - 1 == 0 g[n_] := (2*n - 1)^2 
               /; (n < 4) g[n_] := (2*n - 1)^2 /; (n > 13) && (n < 17) g[n_] := 
               (2*n - 3)^2 /; (n > 4) && (n < 13) g[n_] := (2*n + 3)^2 /; (n >= 
               17) && (n < 19) g[n_] := (2*n + 5)^2 /; (n >= 18) a(n) = g[n]
%t A117580 g[n_] := (n - Floor[n/3])^3 /; Mod[n, 3] - 1 == 0 g[n_] := (2*n - 1)^2 
               /; (n < 4) g[n_] := (2*n - 1)^2 /; (n > 13) && (n < 17) g[n_] := 
               (2*n - 3)^2 /; (n > 4) && (n < 13) g[n_] := (2*n + 3)^2 /; (n >= 
               17) && (n < 19) g[n_] := (2*n + 5)^2 /; (n >= 18) a=Table[g[n], {n, 
               1, 20}]
%Y A117580 Cf. A018226.
%Y A117580 Sequence in context: A020210 A062739 A075109 this_sequence A020308 A108989 
               A068583
%Y A117580 Adjacent sequences: A117577 A117578 A117579 this_sequence A117581 A117582 
               A117583
%K A117580 nonn,uned,probation
%O A117580 0,2
%A A117580 Roger L. Bagula (rlbagulatftn(AT)yahoo.com), Apr 08 2006