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.

A134969 List of pairs of primes that are separated by the equivalent of 2 quadratic intervals. Both primes are greater than their preceding perfect squares by the same amount, or offset. The respective perfect squares can be both odd, in which case the offset is even, or both even, in which case the offset is odd.

Original entry on oeis.org

3, 11, 5, 17, 7, 19, 13, 29, 17, 37, 23, 43, 29, 53, 43, 71, 67, 103, 71, 107, 73, 109, 97, 137
Offset: 1

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Author

Michael M. Ross, Feb 04 2008

Keywords

Examples

			Prime pair 71 and 107 have an odd offset of 7 from 64 and 100:
  Interval 1: 8*8 = 64 + 7 = 71.
  Interval 2: 9*9 = 81 + 7 = 88.
  Interval 3: 10*10 = 100 + 7 = 107.
Prime pair 97 and 137 have an even offset of 16 from 81 and 121:
  Interval 1: 9*9 = 81 + 16 = 97.
  Interval 2: 10*10 = 100 + 16 = 116.
  Interval 3: 11*11 = 121 + 16 = 137.
In all cases there is a complete intermediate quadratic interval (#2).
The pair (11,83), 11-9 = 83-81 = 2, does not work because there are 6 squares in between: 16,25,36,49,64,81.
		

Crossrefs

Cf. A056892.

Formula

PS1 + OfN = P1, PS3 + OfN = P2, where
PS1 = first perfect square,
PS3 = 3rd perfect square,
OfN = an equal positive offset from preceding perfect square, and
P1 and P2 = the prime pair.