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A214058 Least m>0 such that gcd(3^n+m,2^n-m) > 1. 1
2, 4, 1, 16, 2, 3, 3, 1, 1, 10, 3, 22, 2, 4, 1, 1675, 2, 1, 3, 1, 1, 10, 3, 1, 2, 4, 1, 81, 2, 12, 3, 788, 1, 10, 3, 75, 2, 4, 1, 1, 2, 12, 3, 1, 1, 10, 3, 192, 2, 4, 1, 16, 2, 1, 3, 1, 1, 10, 3, 1, 2, 4, 1, 361, 2, 3, 3, 1, 1, 10, 3, 1, 1, 4, 1, 81, 2, 12, 3, 1042, 1, 10, 3, 1, 2 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Clark Kimberling, Table of n, a(n) for n = 1..500

EXAMPLE

gcd(9+1,4-1) = gcd(9+2,4-2) = gcd(9+3, 4-3) = 1 and gcd(9+4, 4-4) > 1, so that a(2) = 4.

MATHEMATICA

b[n_] := 3^n; c[n_] := 2^n; Table[m = 1; While[GCD[b[n] + m, c[n] - m] == 1, m++]; m, {n, 150}]

CROSSREFS

Cf. A214056.

Sequence in context: A172385 A081538 A224783 * A173820 A030043 A045497

Adjacent sequences:  A214055 A214056 A214057 * A214059 A214060 A214061

KEYWORD

nonn,easy

AUTHOR

Clark Kimberling, Jul 24 2012

STATUS

approved

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Last modified May 17 12:55 EDT 2021. Contains 343971 sequences. (Running on oeis4.)