A333250 a(n) = concatenate(n-1, a(n-1)) mod n, with initial condition a(0) = 0.

0, 0, 0, 2, 0, 0, 2, 6, 4, 3, 3, 4, 6, 9, 13, 3, 9, 16, 6, 15, 15, 20, 8, 21, 17, 17, 21, 2, 20, 7, 27, 20, 16, 15, 17, 22, 30, 4, 32, 10, 30, 12, 38, 24, 12, 2, 38, 32, 28, 26, 26, 28, 32, 38, 46, 1, 47, 4, 52, 11, 31, 53, 15, 41, 5, 60, 26, 60, 28, 66, 36, 7, 69, 42, 16, 66, 42, 19, 75, 54, 34

Offset: 0

Author

Andrew Nelson, Mar 13 2020

Keywords

• nonn
• look
• base

Comments

a(n) = 0 for n = 0, 1, 2, 4, 5, 359, 841, 5129, 5180, 5292, 22255, 50109, 85763 (a(n) < 10^6).

a(n) merges with a similar sequence with an odd initial condition (e.g., a(0) = 1) at term a(250).

Examples

			a(2) = concatenate(1, a(1)) mod 2 = concatenate(1, 0) mod 2 = 10 mod 2 = 0.
a(20) = concatenate(19, a(19)) mod 20 = concatenate(19, 15) mod 20 = 1915 mod 20 = 15.
		

Links

• Andrew Nelson, Table of n, a(n) for n = 0..10000

Programs

PARI

lista(nn) = {my(a = 0, list = List()); listput(list, a); for (n=1, nn, a = eval(concat(Str(n-1), a)) % n; listput(list, a);); Vec(list);} \\ Michel Marcus, Mar 17 2020