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A123051
a(2*n-1) = (4*n-3)^(4*n-2) and a(2*n) = (4*n)^(4*n-1), n=1,2,...
1
1, 64, 15625, 2097152, 3486784401, 743008370688, 3937376385699289, 1152921504606846976, 14063084452067724991009, 5242880000000000000000000, 122694327386105632949003612841, 55572324035428505185378394701824
OFFSET
1,2
LINKS
Sergio Silva, Teste Numérico.
EXAMPLE
Sequence gives the following terms: 1^2, 4^3, 5^6, 7^8, 9^10, 12^11, ...
MATHEMATICA
a[n_]:= a[n]= If[EvenQ[n], (2*n)^(2*n-1), (2*n-1)^(2*n)];
Table[a[n], {n, 20}] (* G. C. Greubel, Jul 20 2021 *)
PROG
(PARI) for(k=1, 10, print1((4*k-3)^(4*k-2), ", ", (4*k)^(4*k-1), ", "))
(Sage)
def a(n): return (2*n)^(2*n-1) if (n%2==0) else (2*n-1)^(2*n)
[a(n) for n in (1..20)] # G. C. Greubel, Jul 20 2021
CROSSREFS
Sequence in context: A135788 A016794 A264058 * A064068 A220853 A013781
KEYWORD
nonn
AUTHOR
Herman Jamke (hermanjamke(AT)fastmail.fm), Sep 25 2006
STATUS
approved