A324053 a(n) = 1 if n > 3 and A002322(n) divides n-3, 0 otherwise; Characteristic function of 3-Knödel numbers.

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

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: A025461 A373264 A169674 * A353480 A045698 A106197

Adjacent sequences: A324050 A324051 A324052 * A324054 A324055 A324056

Keyword

nonn

Author

Antti Karttunen, Feb 13 2019

Status

approved