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 A126072 a(n) = least j>n such that one of p(n)#+p(j)#-1 and p(n)#+p(j)#+1 is prime, or 0 if no such prime exists. 0
 2, 3, 4, 5, 6, 7, 9, 9, 15, 11, 13, 13, 18, 20, 29, 19, 23, 21, 21, 21, 23, 32, 27, 42, 28, 30, 30, 34, 37, 77, 33, 74, 59, 45, 53, 45, 38, 46, 43, 47, 55, 44, 47, 54, 76, 48, 49, 50, 69, 56, 60, 0, 66, 68, 94, 57, 69, 84, 86, 73, 65, 73, 71, 114, 70, 91, 98, 80, 72, 84, 79, 76 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS The first 0 is for n=52. Are there others? LINKS EXAMPLE 2+2*3-1=7 so a(1)=2 2*3+2*3*5-1=35 is composite but 2*3+2*3*5+1=37 is prime so a(2)=3 CROSSREFS Sequence in context: A071191 A300903 A097428 * A265570 A265554 A082463 Adjacent sequences:  A126069 A126070 A126071 * A126073 A126074 A126075 KEYWORD nonn AUTHOR Pierre CAMI, Mar 01 2007 STATUS approved

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Last modified June 25 12:36 EDT 2019. Contains 324352 sequences. (Running on oeis4.)