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A120155
a(n) = 10 + floor( (1 + Sum_{j=1..n-1} a(j) )/3 ).
1
10, 13, 18, 24, 32, 42, 56, 75, 100, 133, 178, 237, 316, 421, 562, 749, 999, 1332, 1776, 2368, 3157, 4209, 5612, 7483, 9977, 13303, 17737, 23650, 31533, 42044, 56059, 74745, 99660, 132880, 177173, 236231, 314975, 419966, 559955, 746607
OFFSET
1,1
LINKS
MATHEMATICA
A120155[n_]:= A120155[n]= 10 +Quotient[1 +Sum[A120155[k], {k, n-1}], 3];
Table[A120155[n], {n, 60}] (* G. C. Greubel, Jun 20 2023 *)
PROG
(Magma)
function f(n, a, b)
t:=0;
for k in [1..n-1] do
t+:= a+Floor((b+t)/3);
end for;
return t;
end function;
g:= func< n, a, b | f(n+1, a, b)-f(n, a, b) >;
A120155:= func< n | g(n, 10, 1) >;
[A120155(n): n in [1..60]]; // G. C. Greubel, Jun 20 2023
(SageMath)
@CachedFunction
def A120155(n): return 10 +(1+sum(A120155(k) for k in range(1, n)))//3
[A120155(n) for n in range(1, 61)] # G. C. Greubel, Jun 20 2023
CROSSREFS
KEYWORD
nonn
AUTHOR
Graeme McRae, Jun 10 2006
STATUS
approved