A354813 - OEIS

%I #6 Jun 07 2022 13:01:36

%S 21,33,39,51,57,69,87,93,111,123,129,130,141,159,177,183,190,201,213,

%T 219,231,237,249,267,291,303,309,310,321,327,339,370,381,393,411,417,

%U 430,447,453,471,489,501,519,537,543,573,579,591,597,610,633,669,670,681,687,699,717,723,730,753,771,789,790,807,813

%N Positions of +3's in A346242.

%C a(11) = 130 is the first term that is not a multiple of 3.

%H <a href="/index/Pri#primorialbase">Index entries for sequences related to primorial base</a>

%o (PARI) isA354813(n) = (3==A346242(n));

%Y Cf. A346242.

%K nonn

%O 1,1

%A _Antti Karttunen_, Jun 07 2022