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 A084196 Number of primes q
 0, 0, 1, 1, 3, 0, 2, 1, 5, 2, 2, 0, 3, 1, 6, 3, 6, 0, 1, 7, 0, 3, 6, 4, 1, 2, 2, 6, 0, 3, 3, 5, 2, 3, 3, 3, 0, 1, 9, 2, 9, 1, 8, 0, 3, 3, 1, 4, 6, 0, 3, 11, 0, 8, 2, 8, 6, 3, 0, 2, 1, 5, 3, 7, 0, 2, 1, 0, 5, 1, 2, 13, 2, 0, 3, 10, 3, 0, 2, 0, 11, 0, 11, 2, 5, 5, 6, 0, 4, 2, 6, 13, 2, 5, 2, 13, 4, 4, 1, 0, 1, 4 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,5 COMMENTS a(A049084(A082539(n)))=0, a(A049084(A084197(n)))>0, a(A049084(A084198(n)))=1; LINKS Reinhard Zumkeller, Table of n, a(n) for n = 1..10000 EXAMPLE n=5, prime(5)=11: (11+1) mod (q+1) = 0 for 3 primes q<11: 2, 3, and 5, therefore a(5)=3. PROG (Haskell) a084196 n = a084196_list !! (n-1) a084196_list = f [] a000040_list where    f ps' (p:ps) = length [q | q <- ps', mod (p + 1) (q + 1) == 0] :                   f (p : ps') ps where -- Reinhard Zumkeller, Jan 06 2014 CROSSREFS Cf. A084198, A084200. Sequence in context: A268464 A165066 A034389 * A295041 A127913 A135991 Adjacent sequences:  A084193 A084194 A084195 * A084197 A084198 A084199 KEYWORD nonn AUTHOR Reinhard Zumkeller, May 18 2003 STATUS approved

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Last modified December 3 23:53 EST 2020. Contains 338920 sequences. (Running on oeis4.)