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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 a(n) = A063533(n) - 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 May 18 03:43 EDT 2024. Contains 372618 sequences. (Running on oeis4.)