A284440 - OEIS

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A284440

Smallest number k such that A049559(k) / A187730(k) = n.

1, 21, 91, 65, 451, 217, 2059, 1665, 4699, 2101, 24564, 1729, 74023, 9017, 13051, 4097, 60691, 5833, 278693, 20801, 142003, 10649, 47611, 54145, 116251, 47321, 19684, 21953, 338083, 54901, 501643, 53505, 141571, 219641, 169051, 80353, 386059, 515509, 453259, 16401

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OFFSET

1,2

COMMENTS

For every n, a(n)-1 is not squarefree.

LINKS

Amiram Eldar, Table of n, a(n) for n = 1..450

MATHEMATICA

a[n_]:= Block[{k=1}, While[GCD[k - 1, EulerPhi[k]]/GCD[CarmichaelLambda[k], k - 1] != n, k++]; k]; Table[a[n], {n, 40}] (* Indranil Ghosh, Mar 27 2017 *)

PROG

(PARI) a(n)={my(k=1); while(gcd(k - 1, eulerphi(k))/gcd(lcm(znstar(k)[2]), k - 1) != n, k++); k}; \\ Indranil Ghosh, Mar 27 2017

CROSSREFS

Cf. A284089.

Sequence in context: A268257 A223370 A223363 * A020248 A225705 A259758

Adjacent sequences: A284437 A284438 A284439 * A284441 A284442 A284443

KEYWORD

nonn

AUTHOR

Thomas Ordowski and Altug Alkan, Mar 27 2017

STATUS

approved