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A176337
a(n) = 1 + (1-2^n)*a(n-1) for n > 0, a(0)=0.
4
0, 1, -2, 15, -224, 6945, -437534, 55566819, -14169538844, 7240634349285, -7407168939318554, 15162474818785080039, -62090334382924902759704, 508581928930537878504735465, -8332097741669002063543081123094
OFFSET
0,3
LINKS
MAPLE
A176337 := proc(n)
if n = 0 then
0;
else
1+(1-2^n)*procname(n-1) ;
end if;
end proc: # R. J. Mathar, May 04 2013
MATHEMATICA
a[n_, q_]:= a[n, q]= If[n==0, 0, (1-q^n)*a[n-1, q] +1]; Table[a[n, 2], {n, 0, 15}]
PROG
(PARI) q=2; a(n, q) = if(n==0, 0, 1 -(q^n-1)*a(n-1, q) );
vector(15, n, a(n-1, 2)) \\ G. C. Greubel, Dec 07 2019
(Magma)
function a(n, q)
if n eq 0 then return 0;
else return 1 - (q^n-1)*a(n-1, q);
end if; return a; end function;
[a(n, 2): n in [0..15]]; // G. C. Greubel, Dec 07 2019
(Sage)
def a(n, q):
if (n==0): return 0
else: return 1 - (q^n-1)*a(n-1, q)
[a(n, 2) for n in (0..15)] # G. C. Greubel, Dec 07 2019
(GAP)
a:= function(n, q)
if n=0 then return 0;
else return 1 - (q^n-1)*a(n-1, q);
fi; end;
List([0..15], n-> a(n, 2) ); # G. C. Greubel, Dec 07 2019
CROSSREFS
Cf. A176338.
Sequence in context: A078365 A207037 A218798 * A145168 A184357 A090301
KEYWORD
sign,easy
AUTHOR
Roger L. Bagula, Apr 15 2010
STATUS
approved