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A020247 Strong pseudoprimes to base 21. 1
221, 703, 793, 3781, 7363, 9061, 11647, 13051, 17767, 19669, 19909, 22681, 27133, 30073, 31021, 38503, 41353, 43213, 58829, 79081, 80137, 83569, 88357, 92509, 96049, 104653, 107213, 121987, 127697, 128627, 129889, 130561, 133141, 139679, 139897 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

R. J. Mathar, Table of n, a(n) for n = 1..204

Index entries for sequences related to pseudoprimes

CROSSREFS

Sequence in context: A171427 A211817 A157490 * A177422 A177420 A220737

Adjacent sequences:  A020244 A020245 A020246 * A020248 A020249 A020250

KEYWORD

nonn

AUTHOR

David W. Wilson

STATUS

approved

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Last modified September 21 04:58 EDT 2020. Contains 337267 sequences. (Running on oeis4.)