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A108119
Numbers k such that prime(k) and prime(k+1) are congruent to 1 (mod 10).
0
42, 53, 82, 115, 125, 141, 172, 177, 193, 233, 279, 369, 399, 431, 474, 500, 575, 580, 585, 650, 651, 672, 708, 737, 751, 760, 795, 798, 820, 841, 842, 863, 873, 933, 1019, 1031, 1099, 1112, 1166, 1178, 1225, 1245, 1266, 1312, 1352, 1436, 1463, 1479, 1505
OFFSET
1,1
EXAMPLE
Prime(42)=181, prime(43)=191. This is the first pair of successive primes both ending with 1.
MATHEMATICA
ra=Range[2000]; cnd=Mod[Prime[ # ], 10]==Mod[Prime[ #+1], 10]==1&; se=Select[ra, cnd]
CROSSREFS
Sequence in context: A186456 A181647 A105346 * A175103 A116262 A156394
KEYWORD
nonn
AUTHOR
Zak Seidov, Jun 04 2005
STATUS
approved