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A324053 a(n) = 1 if n > 3 and A002322(n) divides n-3, 0 otherwise; Characteristic function of 3-Knödel numbers. 2
0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0 (list; graph; refs; listen; history; text; internal format)
OFFSET

1

COMMENTS

Characteristic function of A033553, 3-Knödel numbers.

LINKS

Antti Karttunen, Table of n, a(n) for n = 1..100000

Wikipedia, Knödel number

Index entries for characteristic functions

PROG

(PARI)

A002322(n) = lcm(znstar(n)[2]); \\ From A002322

A324053(n) = ((n>3) && 0==((n-3)%A002322(n)));

(PARI) A324053(n) = if(n<4, 0, my(p=factor(n)); for(i=1, matsize(p)[1], if( (n-3)%eulerphi(p[i, 1]^p[i, 2]), return(0)); ); 1); \\ After Max Alekseyev's code in A033553

CROSSREFS

Cf. A002322, A033553.

Sequence in context: A037824 A025461 A169674 * A045698 A106197 A011722

Adjacent sequences:  A324050 A324051 A324052 * A324054 A324055 A324056

KEYWORD

nonn

AUTHOR

Antti Karttunen, Feb 13 2019

STATUS

approved

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Last modified January 20 00:08 EST 2022. Contains 350467 sequences. (Running on oeis4.)