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 A247906 a(n) = n-th pseudoprime to base n. 0
 561, 286, 341, 781, 1105, 1105, 133, 364, 703, 793, 1105, 1099, 1891, 6541, 1271, 3991, 1649, 1849, 3059, 7363, 2047, 1738, 4537, 1128, 3145, 2993, 5365, 4069, 4097, 7421, 2465, 11305, 2937, 16589, 4495, 2044, 6601, 26885, 13073, 6892, 22945, 3885, 8695, 10879 (list; graph; refs; listen; history; text; internal format)
 OFFSET 2,1 LINKS Table of n, a(n) for n=2..45. EXAMPLE a(2) = A001567(2) = 561. a(3) = A005935(3) = 286. PROG (PARI) for(n=2, 20, i=0; forcomposite(c=2, 1e9, if(Mod(n, c)^(c-1)==1, i++; if(i==n, print1(c, ", "); i=0; break({1}))); if(c==1e9, print1(">1e9, ")))) CROSSREFS Cf. A007535, A098650. Cf. Pseudoprimes to base b: A001567 (b=2), A005935 (b=3), A020136 (b=4), A005936 (b=5), A005937 (b=6), A005938 (b=7), A020137 (b=8), A020138 (b=9). Sequence in context: A265261 A234936 A274443 * A278338 A184047 A344673 Adjacent sequences: A247903 A247904 A247905 * A247907 A247908 A247909 KEYWORD nonn AUTHOR Felix Fröhlich, Sep 26 2014 STATUS approved

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Last modified December 5 05:37 EST 2023. Contains 367575 sequences. (Running on oeis4.)