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 A212601 Intersection of A001567 and A212502. 2
 4033, 6601, 8321, 15841, 25761, 29341, 41041, 46657, 75361, 115921, 162401, 172081, 252601, 294409, 314821, 332949, 401401, 410041, 488881, 530881, 552721, 642001, 721801, 873181, 934021, 1004653, 1207361, 1461241, 1876393, 1909001, 2081713, 2085301, 2113921 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Only 1 (mod 4) numbers have been found. LINKS Amiram Eldar, Table of n, a(n) for n = 1..10000 MATHEMATICA t[n_] := Which[Mod[n, 4] == 3, n + 1, Mod[n, 4] == 1, n - 1, True, n]; Select[1 + Range[99000], PowerMod[2, # - 1, #] == 1 && !PrimeQ[#] && Im[PowerMod[1 + 2I, t[#], #]] == 0 &] CROSSREFS Cf. A201629. Cf. A001567 (pseudoprimes to base 2). Cf. A212502 (pseudoprimes to base 1+2i). Sequence in context: A329881 A234838 A234834 * A060896 A371757 A206617 Adjacent sequences: A212598 A212599 A212600 * A212602 A212603 A212604 KEYWORD nonn AUTHOR José María Grau Ribas, May 22 2012 STATUS approved

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Last modified May 28 15:12 EDT 2024. Contains 372916 sequences. (Running on oeis4.)