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A200982 Numbers n such that 1^(lambda(n)/2) + 2^(lambda(n)/2) + ... + (n - 1)^(lambda(n)/2) = 0 (mod n), where lambda is the Carmichael reduced totient function. 0
1, 3, 5, 7, 9, 11, 13, 17, 19, 21, 23, 25, 27, 28, 29, 31, 33, 36, 37, 41, 43, 44, 47, 49, 53, 56, 57, 59, 61, 63, 65, 67, 69, 71, 72, 73, 76, 77, 79, 81, 83, 84, 88, 89, 92, 93, 97, 99, 101, 103, 107, 108, 109, 113, 121, 124, 125, 127, 129, 131, 132, 133 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Conjecture: The asymptotic density is zero.

LINKS

Table of n, a(n) for n=1..62.

MATHEMATICA

Select[Range[200], (Mod[Sum[PowerMod[j, CarmichaelLambda[#]/2, #], {j, #}], #] == 0) &]

CROSSREFS

Cf. A002322, the reduced totient function.

Sequence in context: A247428 A184591 A033040 * A084820 A324846 A324760

Adjacent sequences:  A200979 A200980 A200981 * A200983 A200984 A200985

KEYWORD

nonn

AUTHOR

José María Grau Ribas, Nov 25 2011

STATUS

approved

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Last modified March 24 11:49 EDT 2019. Contains 321448 sequences. (Running on oeis4.)