A120138 -id:A120138 - cp's OEIS frontend

A120137 a(n) = 8 + floor( (1 + Sum_{j=1..n-1} a(j)) / 2).

8, 12, 18, 27, 41, 61, 92, 138, 207, 310, 465, 698, 1047, 1570, 2355, 3533, 5299, 7949, 11923, 17885, 26827, 40241, 60361, 90542, 135813, 203719, 305579, 458368, 687552, 1031328, 1546992, 2320488, 3480732, 5221098, 7831647, 11747471, 17621206

Offset: 1

Graeme McRae, Jun 10 2006

nonn

G. C. Greubel, Table of n, a(n) for n = 1..1000

Cf. A073941, A072493, A112088, A120134 - A120136, A120138 - A120209.

a[n_]:= a[n]= 8 +Floor[(1 +Sum[a[k], {k,n-1}])/2];
Table[a[n], {n,60}] (* G. C. Greubel, May 08 2023 *)
nxt[{t_,a_}]:=Module[{c=8+Floor[(1+t)/2]},{t+c,c}]; NestList[nxt,{8,8},40][[;;,2]] (* Harvey P. Dale, Sep 10 2023 *)

@CachedFunction
def A120137(n): return 8 +(1 +sum(A120137(k) for k in range(1,n)))//2
[A120137(n) for n in range(1,60)] # G. C. Greubel, May 08 2023

A120139 a(n) = 11 + floor( (1 + Sum_{j=1..n-1} a(j)) / 2).

Original entry on oeis.org

11, 17, 25, 38, 57, 85, 128, 192, 288, 432, 648, 972, 1458, 2187, 3280, 4920, 7380, 11070, 16605, 24908, 37362, 56043, 84064, 126096, 189144, 283716, 425574, 638361, 957542, 1436313, 2154469, 3231704, 4847556, 7271334, 10907001, 16360501

Offset: 1

Graeme McRae, Jun 10 2006

nonn

G. C. Greubel, Table of n, a(n) for n = 1..1000

Cf. A073941, A072493, A112088, A120134 - A120138, A120140 - A120209.

a[n_]:= a[n]= 11 +Quotient[1 + Sum[a[k], {k,n-1}], 2];
Table[a[n], {n,60}] (* G. C. Greubel, May 08 2023 *)

@CachedFunction
def A120139(n): return 11 +(1 +sum(A120139(k) for k in range(1,n)))//2
[A120139(n) for n in range(1,60)]  # G. C. Greubel, May 08 2023

cp's OEIS Frontend

A120137 a(n) = 8 + floor( (1 + Sum_{j=1..n-1} a(j)) / 2).

Views

Author

Keywords

Links

Crossrefs

Programs

Mathematica

SageMath