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R. J. Mathar, Table of n, a(n) for n = 1..237
Eric Weisstein's World of Mathematics, Strong Pseudoprime
Index entries for sequences related to pseudoprimes
Cf. A020233 (base 7).
Sequence in context: A037548 A238275 A036731 * A154996 A128195 A103459
Adjacent sequences: A020231 A020232 A020233 * A020235 A020236 A020237
David W. Wilson