A178794These are the x coordinates of the isolated visible lattice points in the plane.

21, 99, 115, 369, 495, 475, 195, 259, 265, 225, 375, 741, 741, 649, 323, 377, …

The first 2 terms appear at position 1,426.

…7823547816360093417216412199245863150302861829745557…
position 1,426
termsstringfirst positionoccurrences
1219310,000,534
221991,42699,588
3219911512,349,77699
42199115369not within 1,000,000,0000

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