A000487Number of permutations of length n with exactly two valleys.

16, 272, 2880, 24576, 185856, 1304832, 8728576, 56520704, 357888000, 2230947840, 13754155008, 84134068224, 511780323328, 3100738912256, 18733264797696, 112949304754176, …

The first term appear at position 40.

…23846264338327950288419716939937510582097494459230…
position 40
termsstringfirst positionoccurrences
1164010,001,877
216272407,68910,142
3162722880not within 1,000,000,0000

Searched the first 1,000,000,000 digits. Strings longer than 12 digits are not indexed.