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A141162 Smallest k such that lambda(k) = n, or 0 if there is no such k. 2
1, 3, 0, 5, 0, 7, 0, 32, 0, 11, 0, 13, 0, 0, 0, 17, 0, 19, 0, 25, 0, 23, 0, 224, 0, 0, 0, 29, 0, 31, 0, 128, 0, 0, 0, 37, 0, 0, 0, 41, 0, 43, 0, 115, 0, 47, 0, 119, 0, 0, 0, 53, 0, 81, 0, 928, 0, 59, 0, 61, 0, 0, 0, 256, 0, 67, 0, 0, 0, 71, 0, 73, 0, 0, 0, 0, 0, 79, 0, 187, 0, 83, 0, 203, 0, 0, 0, 89, 0, 209, 0, 235, 0, 0, 0, 97, 0 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Sequence A002174 gives the n such that a(n) > 0. Removing the zeros from this sequence produces A002396. Note that some n appear only for large k. For example, 728 does not appear until k=49184. See A143407 for the largest k that produces a particular value of the lambda function. See A143408 for the number of times each value occurs. - T. D. Noe, Mar 17 2011

LINKS

Table of n, a(n) for n=1..97.

FORMULA

a(A002174(n)) = A002396(n).

EXAMPLE

a(8) = 32 because lambda(32) = 8.

MAPLE

with(numtheory):for k from 1 to 100 do:id:=0:for n from 1 to 1000 while(id=0)

  do: if lambda(n) = k then id:=1:printf(`%d, `, n):else fi:od:if id=0 then printf(`%d, `, 0):else fi:od:

MATHEMATICA

nn = 100; t = Table[0, {nn}]; Do[c = CarmichaelLambda[k]; If[c <= nn && t[[c]] == 0, t[[c]] = k], {k, 1000}]; t

CROSSREFS

Cf. A002174, A002322 (Carmichael lambda function), A002396, A143407, A143408.

Sequence in context: A071649 A210524 A049283 * A160035 A281648 A210451

Adjacent sequences:  A141159 A141160 A141161 * A141163 A141164 A141165

KEYWORD

nonn

AUTHOR

Michel Lagneau, Mar 17 2011

STATUS

approved

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Last modified November 19 08:40 EST 2018. Contains 317347 sequences. (Running on oeis4.)