A385951 Number of digits in 5^(n!).

1, 1, 2, 5, 17, 84, 504, 3523, 28183, 253643, 2536423, 27900646, 334807751, 4352500756, 60935010579, 914025158672, 14624402538737, 248614843158529, 4475067176853513, 85026276360216746, 1700525527204334919, 35711036071291033288, 785642793568402732327

Offset: 0

Author

Vincenzo Librandi, Jul 27 2025

Keywords

• nonn
• base

Crossrefs

Cf. A055642, A220078.

Subsequence of A210435.

Programs

Mathematica

Array[Floor[#! Log10@5+1]&,22]

Formula

a(n) = A055642(A220078(n)).