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A045892
Solutions s to the equation 1=s*prime(n)+t*prime(n+1) with |s| as small as possible.
1
-1, 2, 3, -3, 6, 4, 9, -6, -5, 15, 6, 10, 21, -12, -9, -10, 30, 11, -18, 36, 13, -21, -15, 12, 25, 51, -27, 54, 28, 9, -33, -23, 69, -15, 75, 26, 27, -42, -29, -30, 90, 19, 96, 49, 99, -88, -93, -57, 114, 58, -40, 120, 25, -43, -44, -45, 135, 46, 70, 141, -88
OFFSET
1,2
MATHEMATICA
Table[ Part[ Part[ ExtendedGCD[ Prime[ i ], Prime[ i+1 ] ], 2 ], 1 ], {i, 50} ]
PROG
(PARI) a(n)=gcdext(prime(n), prime(n+1))[1] \\ Charles R Greathouse IV, Nov 16 2015
CROSSREFS
Cf. A045893.
Sequence in context: A062774 A372808 A266286 * A160791 A377505 A115973
KEYWORD
sign
EXTENSIONS
Name made stricter and terms updated and extended by Sean A. Irvine, Mar 24 2021
STATUS
approved