A327277 - OEIS

%I #40 Oct 30 2021 17:21:03

%S 2,3,2,3,5,2,3,5,7,11,2,3,5,7,11,13,17,2,3,5,7,11,13,17,19,23,29,31,2,

%T 3,5,7,11,13,17,19,23,29,31,37,41,2,3,5,7,11,13,17,19,23,29,31,37,41,

%U 43,47,53,59,2,3,5,7,11,13,17,19,23,29,31,37,41,43,47,53,59,61,67

%N Irregular triangle read by rows in which row n lists the first prime(n) primes.

%H Harvey P. Dale, <a href="/A327277/b327277.txt">Table of n, a(n) for n = 1..1000</a>

%e Table begins:

%e   2, 3;

%e   2, 3, 5;

%e   2, 3, 5, 7, 11;

%e   2, 3, 5, 7, 11, 13, 17;

%e   2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31;

%e   2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31, 37, 41;

%e   ...

%t m = 8; p = Array[Prime, Prime[m]]; Join @@ (p[[1 ;; p[[#]]]] & /@ Range[m]) (* _Amiram Eldar_, Sep 24 2019 *)

%t Table[Take[Prime[Range[Prime[n]]],n],{n,Prime[Range[10]]}]//Flatten (* _Harvey P. Dale_, Oct 30 2021 *)

%Y Right border gives A006450.

%Y A138117 is essentially the same triangle.

%K nonn,tabf

%O 1,1

%A _Frederick John Bernet III_, Sep 15 2019