A340989 - OEIS

%I #5 Feb 03 2021 23:20:28

%S 2,4,7,9,18,21,24,29,32,49,51,55,60,62,72,85,92,95,104,107,110,118,

%T 127,135,146,164,166,169,176,179,202,205,218,220,232,237,247,262,265,

%U 279,287,290,303,306,309,313,328,339,347,350,355,363,366,399,403,412,418,424,433,441,443,456,476,479

%N The index of A337182 where prime(n) first appears as a factor.

%C a(1) = 2 as A337182(2) = 2 which contains prime(1) = 2 as a factor.

%C a(2) = 4 as A337182(4) = 6 which contains prime(2) = 3 as a factor.

%C a(3) = 7 as A337182(7) = 10 which contains prime(3) = 5 as a factor.

%C a(4) = 9 as A337182(9) = 14 which contains prime(4) = 7 as a factor.

%Y Cf. A337182, A338222, A098550, A336957, A064413, A027746.

%K nonn

%O 1,1

%A _Scott R. Shannon_, Feb 01 2021