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 A271873 Square array A(n, k) read by antidiagonals downwards: smallest base-n Fermat pseudoprime with k distinct prime factors for k, n >= 2. 1
 341, 561, 91, 11305, 286, 15, 825265, 41041, 435, 124, 45593065, 825265, 11305, 561, 35 (list; table; graph; refs; listen; history; text; internal format)
 OFFSET 2,1 COMMENTS The array A(n, k) starts as follows:    k  =  2    3     4        5         6 n = 2: 341  561 11305   825265  45593065 n = 3:  91  286 41041   825265 130027051 n = 4:  15  435 11305   418285  30534805 n = 5: 124  561 41041  2203201  68800501 n = 6:  35 1105 25585   682465  12306385 LINKS PROG (PARI) minpsp(n, k) = forcomposite(c=1, , if(Mod(n, c)^(c-1)==1, if(omega(c)==k, return(c)))) a(n, k) = for(x=2, n, for(y=2, k, print1(minpsp(x, y), ", ")); print("")) a(6, 6) \\ print array up to n = 6, k = 6 CROSSREFS Cf. A007011 (row n=2), A271874. Sequence in context: A025345 A337715 A253038 * A001567 A178723 A210993 Adjacent sequences:  A271870 A271871 A271872 * A271874 A271875 A271876 KEYWORD nonn,tabl,more AUTHOR Felix FrÃ¶hlich, Apr 16 2016 STATUS approved

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Last modified April 13 01:36 EDT 2021. Contains 342934 sequences. (Running on oeis4.)