A226073 Numbers k such that triangular(k)-1 is a square and triangular(k)+1 is a prime number.
1, 4, 148, 5821348, 13748537282247342677718148, 49900608324196518198677680899235165296598423281799348
Offset: 1
This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
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