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n^2 followed by n^3 followed by n followed by n^4.
1

%I #17 Sep 08 2022 08:45:20

%S 1,1,1,1,4,8,2,16,9,27,3,81,16,64,4,256,25,125,5,625,36,216,6,1296,49,

%T 343,7,2401,64,512,8,4096,81,729,9,6561,100,1000,10,10000,121,1331,11,

%U 14641,144,1728,12,20736,169,2197,13,28561,196,2744,14,38416,225,3375

%N n^2 followed by n^3 followed by n followed by n^4.

%H Vincenzo Librandi, <a href="/A110653/b110653.txt">Table of n, a(n) for n = 1..4000</a>

%F a(n) = floor((n+3)/4)^((-2*(n mod 4)^3+9*(n mod 4)^2 - 11*(n mod 4) + 8)/2). - _Luce ETIENNE_, Apr 07 2018

%F From _Chai Wah Wu_, Jan 11 2020: (Start)

%F a(n) = 5*a(n-4) - 10*a(n-8) + 10*a(n-12) - 5*a(n-16) + a(n-20) for n > 20.

%F G.f.: x*(-x^15 + x^14 + x^13 - x^12 - 11*x^11 - 3*x^10 + 3*x^9 + x^8 - 11*x^7 + 3*x^6 - 3*x^5 + x^4 - x^3 - x^2 - x - 1)/((x - 1)^5*(x + 1)^5*(x^2 + 1)^5). (End)

%t Flatten[Table[{n^2, n^3, n, n^4}, {n, 40}]] (* _Vincenzo Librandi_, Feb 06 2013 *)

%o (Magma) &cat[[n^2, n^3, n, n^4]: n in [1..20]]; // _Vincenzo Librandi_, Feb 06 2013

%Y Cf. A000463; A109588; A109594.

%Y Cf. A010873.

%K nonn,easy

%O 1,5

%A _Mohammad K. Azarian_, Sep 14 2005