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 A252094 First member of a pair (A,B) to define the n-th Zeisel number, cf. A051015. 3
 1, 4, 1, 2, 3, 2, 10, 2, 6, 4, 13, 8, 3, 2, 25, 5, 9, 28, 1, 6, 5, 17, 34, 15, 9, 23, 8, 49, 55, 12, 4, 33, 14, 2, 24, 36, 25, 2, 26, 4, 2, 42, 29, 11, 8, 2, 10, 4, 88, 6, 47, 32, 48, 20, 94, 37, 23, 57, 24, 3, 5, 115, 6, 118, 9, 44, 3, 46, 68, 5, 30, 139, 50, 10, 51, 14, 77, 20, 54, 2 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS Let p(0) = 1 and p(i+1) = A*p(i) + B, if p(i) is prime for i = 1..k, then z = p(1) * ... * p(k) is called a Zeisel number. LINKS Table of n, a(n) for n=1..80. OEIS Wiki, Zeisel numbers Eric Weisstein's World of Mathematics, Zeisel Number. Wikipedia, Zeisel number EXAMPLE . n | A=a(n) B=A252095(n) | p(1) p(2) p(3) | A051015(n) . ---+------------------------+------------------------------ . 1 | 1 2 | 3 5 7 | 105 . 2 | 4 -1 | 3 11 43 | 1419 . 3 | 1 6 | 7 13 19 | 1729 . 4 | 2 3 | 5 13 29 | 1885 . 5 | 3 2 | 5 17 53 | 4505 . 6 | 2 5 | 7 19 43 | 5719 . 7 | 10 -7 | 3 23 223 | 15387 . 8 | 2 9 | 11 31 71 | 24211 . 9 | 6 -1 | 5 29 177 | 25085 . 10 | 4 3 | 7 31 141 | 27449 . 11 | 13 -10 | 3 29 367 | 31929 . 12 | 8 -3 | 5 37 295 | 54205 . PROG (Haskell) a252094 n = a252094_list !! (n-1) (a252094_list, a252095_list) = unzip \$ f 3 where f x = if z then (q, p - q) : f (x + 2) else f (x + 2) where z = 0 `notElem` ds && length ds > 2 && all (== 0) (zipWith mod (tail ds) ds) && all (== q) qs q:qs = (zipWith div (tail ds) ds) ds = zipWith (-) (tail ps) ps ps = 1 : ps'; ps'@(p:_) = a027746_row x CROSSREFS Cf. A051015, A027746, A252095 (B values). Sequence in context: A321091 A064124 A106654 * A196138 A198185 A197889 Adjacent sequences: A252091 A252092 A252093 * A252095 A252096 A252097 KEYWORD nonn AUTHOR Reinhard Zumkeller, Dec 15 2014 STATUS approved

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Last modified June 8 13:50 EDT 2023. Contains 363165 sequences. (Running on oeis4.)