A222379 - cp's OEIS frontend

A222379 Number of distinct functions f representable as x -> x^x^...^x with n x's and parentheses inserted in all possible ways giving result f(0)=0, with conventions that 0^0=1^0=1^1=1, 0^1=0.

n	a(n)
0	0
1	1
2	0
3	1
4	1
5	4
6	6
7	19
8	38
9	107
10	247
11	668
12	1666
13	4468
14	11603
15	31210
16	83044
17	224893
18	607658
19	1657966
20	4528193
21	12441364
22	34254321
23	94696165
24	262389581
25	729258392
26	2031264865
27	5671570468
28	15867219821
29	44480785907
30	124913622052
31	351393746745
32	990048748684

[0, 1, 0, 1, 1, 4, 6, 19, 38, 107, 247, 668, 1666, 4468, 11603, 31210, 83044, 224893, 607658, 1657966, 4528193, 12441364, 34254321, 94696165, 262389581, 729258392, 2031264865, 5671570468, 15867219821, 44480785907, 124913622052, 351393746745, 990048748684]

cp's OEIS Frontend

A222379 Number of distinct functions f representable as x -> x^x^...^x with n x's and parentheses inserted in all possible ways giving result f(0)=0, with conventions that 0^0=1^0=1^1=1, 0^1=0.

Table of values

List of values