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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. 0
3, 11, 5, 17, 7, 19, 13, 29, 17, 37, 23, 43, 29, 53, 43, 71, 67, 103, 71, 107, 73, 109, 97, 137 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..24.

Michael M. Ross What Are Odd Squared, or Biquadratic, Paired Primes?

Diagram of paired primes The diagram shows how two perfect pairs partially overlap: 23 and 43 span perfect squares 25 and 36; 29 and 53 span perfect squares 36 and 49.

VBA source codeProvides an Excel visualization of the odd-offset prime pairs and colocation with twin primes.

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 P1 and P2 = the prime pair

EXAMPLE

For example, 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

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

In all cases there is a complete intermediate quadratic interval (#2).

PROG

Excel VBA available at http://www.naturalnumbers.org/quadprimes.html#code Demonstrates odd-offset prime-pair distribution with associated twin primes. Limitations: -Only the subset of paired primes for even perfect squares with odd offsets are demonstrated. -Because of the 256-column limitation for an Excel worksheet, data in rows after perfect square 484 are not complete. -Only twin primes that are also paired primes are outlined (in red).

CROSSREFS

Sequence in context: A084466 A084462 A156320 * A139686 A212782 A130537

Adjacent sequences:  A134966 A134967 A134968 * A134970 A134971 A134972

KEYWORD

nonn,tabf

AUTHOR

Michael M. Ross, Feb 04 2008

STATUS

approved

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Last modified July 25 15:47 EDT 2014. Contains 244915 sequences.