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Fifth row of number array A084061.
4

%I #6 Sep 08 2022 08:45:10

%S 1,1,8,63,656,8525,133120,2430547,50839808,1199150649,31495553024,

%T 911770726823,28846956187648,990358890251653,36670756251238400,

%U 1456804472261953275,61808742217201811456,2789456491560247772657

%N Fifth row of number array A084061.

%H G. C. Greubel, <a href="/A084096/b084096.txt">Table of n, a(n) for n = 0..300</a>

%F a(n) = ((n - sqrt(4))^n + (n + sqrt(4))^n)/2 = ((n+2)^n + (n-2)^n)/2.

%p seq( ((n-2)^n + (n+2)^n)/2, n=0..20); # _G. C. Greubel_, Jan 11 2020

%t Table[((n+2)^n + (n-2)^n)/2, {n,0,20}] (* _G. C. Greubel_, Jan 11 2020 *)

%o (PARI) vector(21, n, ((n-3)^(n-1) + (n+1)^(n-1))/2 ) \\ _G. C. Greubel_, Jan 11 2020

%o (Magma) [((n-2)^n + (n+2)^n)/2: n in [0..20]]; // _G. C. Greubel_, Jan 11 2020

%o (Sage) [((n-2)^n + (n+2)^n)/2 for n in (0..20)] # _G. C. Greubel_, Jan 11 2020

%o (GAP) List([0..20], n-> ((n-2)^n + (n+2)^n)/2); # _G. C. Greubel_, Jan 11 2020

%Y Cf. A084061, A084062, A084063, A084064, A084065, A084095.

%K easy,nonn

%O 0,3

%A _Paul Barry_, May 11 2003