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A181637 Numbers n such that lambda(n) = reversal(n). 0
1, 40, 210, 8656341, 86563410 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Lambda(n) is the Carmichael lambda function A002322.

LINKS

Table of n, a(n) for n=1..5.

EXAMPLE

210 is in the sequence because lambda(210)= reversal(210) = 12.

MATHEMATICA

Do[If[CarmichaelLambda [n] == FromDigits[Reverse[IntegerDigits[n]]], Print[n]], {n, 1, 10^8}]

PROG

(PARI) isok(n) = lcm(znstar(n)[2]) == subst(Polrev(digits(n)), x, 10); \\ Michel Marcus, Mar 18 2016

CROSSREFS

Cf. A002322, A004086.

Sequence in context: A077818 A247405 A235270 * A111176 A072108 A218404

Adjacent sequences: A181634 A181635 A181636 * A181638 A181639 A181640

KEYWORD

nonn,base,more

AUTHOR

Michel Lagneau, Nov 18 2010

STATUS

approved

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Last modified February 3 11:40 EST 2023. Contains 360034 sequences. (Running on oeis4.)