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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
Wikipedia, Knödel number
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
Sequence in context: A037824 A025461 A169674 * A353480 A045698 A106197
KEYWORD
nonn
AUTHOR
Antti Karttunen, Feb 13 2019
STATUS
approved

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Last modified April 23 11:07 EDT 2024. Contains 371905 sequences. (Running on oeis4.)