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A184417 p^2 + (p+2)^2 - 1 where (p,p+2) is the n-th twin prime pair. 1
33, 73, 289, 649, 1801, 3529, 7201, 10369, 20809, 23329, 38089, 45001, 64801, 73729, 78409, 103969, 115201, 145801, 159049, 194689, 242209, 352801, 373249, 426889, 544969, 649801, 720001, 763849, 824329, 871201, 1312201, 1351369, 1371169, 1472329, 1555849, 2080801, 2130049, 2205001, 2255689, 2384929, 2654209 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

This seems to have a disproportionately high probability of generating a prime number.

LINKS

Table of n, a(n) for n=1..41.

FORMULA

Prime numbers in A063533 - 1.

EXAMPLE

a(1) = [prime(1)]^2 + [prime(1)+2]^2 - 1 = 3^2 + [3+2]^2 - 1 = 33

a(2) = [prime(2)]^2 + [prime(2)+2]^2 - 1 = 5^2 + [5+2]^2 - 1 = 73

a(3) = [prime(3)]^2 + [prime(3)+2]^2 - 1 = 11^2 + [11+2]^2 - 1 = 289

MATHEMATICA

Total/@(Select[Partition[Prime[Range[500]], 2, 1], #[[2]]-#[[1]]==2&]^2)-1  (* Harvey P. Dale, Feb 24 2011 *)

CROSSREFS

Sequence in context: A015722 A103046 A063868 * A240884 A049012 A137187

Adjacent sequences:  A184414 A184415 A184416 * A184418 A184419 A184420

KEYWORD

nonn

AUTHOR

Robert Mohr, Feb 13 2011

STATUS

approved

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Last modified September 25 18:20 EDT 2017. Contains 292499 sequences.