A130336 - OEIS

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A130336

Record values in A130335.

1, 2, 7, 10, 13, 22, 31, 37, 58, 79, 82, 94, 109, 118, 157, 178, 193, 214

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OFFSET

1,2

LINKS

Table of n, a(n) for n=1..18.

FORMULA

a(n) = A130335(A130337(n)).

A130335(k) < a(n) for k < A130337(n).

MATHEMATICA

f[n_] := Block[{k = 1}, While[ GCD[n(n + 1)/2, (n + k)(n + k + 1)/2] != 1, k++ ]; k]; t = Table[0, {1000}]; Do[a = f@n; If[a < 1001 && t[[a]] == 0, t[[a]] = n; Print[{a, n}], If[a > 1000, Print[{"Over 1000", n}]]], {n, 2^31 - 1}] (* Robert G. Wilson v, Jun 03 2007 *)

CROSSREFS

CF. A130335, A130337.

Sequence in context: A203621 A297832 A003158 * A303741 A085303 A304799

Adjacent sequences: A130333 A130334 A130335 * A130337 A130338 A130339

KEYWORD

nonn,more

AUTHOR

Reinhard Zumkeller, May 28 2007

EXTENSIONS

a(13)-a(16) from Robert G. Wilson v, Jun 03 2007

Added a(17) and corrected a(12) by Chai Wah Wu, Sep 16 2021

a(18) from Chai Wah Wu, Sep 23 2021

STATUS

approved