A139806 - cp's OEIS frontend

A139806 a(n)=a(n-1)+a(n-2)+a(n-3)+2a(n-4), a(0)=1, a(1)=3, a(2)=7, a(3)=15.

n	a(n)
0	1
1	3
2	7
3	15
4	27
5	55
6	111
7	223
8	443
9	887
10	1775
11	3551
12	7099
13	14199
14	28399
15	56799
16	113595
17	227191
18	454383
19	908767
20	1817531
21	3635063
22	7270127
23	14540255
24	29080507
25	58161015
26	116322031
27	232644063
28	465288123
29	930576247
30	1861152495
31	3722304991
32	7444609979
33	14889219959

[1, 3, 7, 15, 27, 55, 111, 223, 443, 887, 1775, 3551, 7099, 14199, 28399, 56799, 113595, 227191, 454383, 908767, 1817531, 3635063, 7270127, 14540255, 29080507, 58161015, 116322031, 232644063, 465288123, 930576247, 1861152495, 3722304991, 7444609979, 14889219959]

cp's OEIS Frontend

A139806 a(n)=a(n-1)+a(n-2)+a(n-3)+2a(n-4), a(0)=1, a(1)=3, a(2)=7, a(3)=15.

Table of values

List of values