A063424 - cp's OEIS frontend

A063424 a(1) = 10, a(n) = concatenation of two closest factors of a(n-1) whose product equals a(n-1) or if a(n-1) is a prime then the concatenation of 1 and a(n-1).

n	a(n)
1	10
2	25
3	55
4	511
5	773
6	1773
7	9197
8	17541
9	91949
10	143643
11	347881
12	3311051
13	13311051
14	35433757
15	71499067
16	72619847
17	74179791
18	82678973
19	613313481
20	1551395431
21	1679289793
22	4339053251
23	6529966449
24	9370214693
25	71338602099
26	222407320757

[10, 25, 55, 511, 773, 1773, 9197, 17541, 91949, 143643, 347881, 3311051, 13311051, 35433757, 71499067, 72619847, 74179791, 82678973, 613313481, 1551395431, 1679289793, 4339053251, 6529966449, 9370214693, 71338602099, 222407320757]

cp's OEIS Frontend

A063424 a(1) = 10, a(n) = concatenation of two closest factors of a(n-1) whose product equals a(n-1) or if a(n-1) is a prime then the concatenation of 1 and a(n-1).

Table of values

List of values