A370255 (n*10)^(n*10) omitting its rightmost trailing 0's.

1, 1, 1048576, 205891132094649, 1208925819614629174706176, 88817841970012523233890533447265625, 48873677980689257489322752273774603865660850176, 143503601609868434285603076356671071740077383739246066639249

Offset: 0

Author

Marco Ripà, Feb 13 2024

Keywords

• nonn
• easy
• base

Examples

			a(0) = A004151(0^0) = A004151(1) = 1.
a(2) = 1048576 since 20^20 = 104857600000000000000000000.
		

Links

• Marco Ripà, Congruence speed of tetration bases ending with 0, arXiv:2402.07929 [math.NT], 2024.

Crossrefs

Cf. A000312, A002489, A004151, A008592, A369771, A369826.

Programs

Python

def A370255(n):
    if n == 0: return 1
    m = n
    a, b = divmod(m,10)
    while not b:
        m = a
        a, b = divmod(m,10)
    return m**(10*n) # Chai Wah Wu, Feb 20 2024

Formula

a(n) = A004151((n*10)^(n*10)).

a(n) = A004151(n)^(n*10), for n >= 1.