A275587 a(1) = 0; thereafter a(n) = s^s where s = Sum_{k=1..n-1} a(k).
0, 1, 1, 4, 46656
Offset: 1
Keywords
Programs
-
Mathematica
a[0] = 0; a[1] = 1; a[n_] := a[n] = #^# &@ Sum[a[k], {k, 1, n - 1}]; Table[a[n], {n, 0, 5}] (* Michael De Vlieger, Aug 04 2016 *) -
PARI
a(n) = local(s); if(n==1, 0, if(n>1, s = sum(k=1, n - 1, a(k)); s^s))
Comments