cp's OEIS Frontend

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.

A347280 Let P1>3, P2, P3, P4 be 4 consecutive primes with P3-P2 = 2. a(n) = P2 is the earliest occurrence of the 4-tuple with min(P2-P1, P4-P3) = 2*n, or 0 if no such constellation exists.

Original entry on oeis.org

11, 29, 0, 419, 521, 0, 1931, 6449, 0, 10037, 43541, 0, 10007, 28349, 0, 107507, 280409, 0, 261167, 173429, 0, 569321, 913637, 0, 1598447, 1789091, 0, 1349531, 5317451, 0, 17282051, 25844561, 0, 10851161, 28582787, 0, 36126917, 14318657, 0, 60117947, 42062717
Offset: 2

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Author

Hugo Pfoertner, Sep 03 2021

Keywords

Comments

The "irregular" constellation 3, 5, 7, 11 is intentionally excluded.

Examples

			a(2) = 11, because min(11-7, 17-13) = 4 is the earliest occurrence of the minimum gap of 2*2 = 4 adjacent to a pair of twin primes.
a(3) = 29: the constellation 23, 29, 31, 37 has min(29-23, 37-31) = 2*3 = 6, whereas the preceding constellations 7, 11, 13, 19, and 13, 17, 19, 23 don't yield a minimum of 6.
a(5) = 419: 409, 419, 421, 431 leads to the earliest occurrence of the minimum adjacent gap of 2*5.
		

Crossrefs

Subset of A001359.