A002303Generalized tangent numbers.

16, 272, 3968, 56320, 814080, 12207360, 191431680, 3149752320, 54428774400, 987559372800, 18797300121600, 374883257548800, 7822865085235200, 170560590520320000, 3879770715684864000, 91945674412720128000

The first term appear at position 40.

…23846264338327950288419716939937510582097494459230…
position 40
termsstringfirst positionoccurrences
1164010,001,877
216272407,68910,142
3162723968not within 1,000,000,0000

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