A161535 - OEIS

A161535

Array read by antidiagonals: Row n contains the positive multiples of the first n primes.

%I #10 Feb 24 2019 21:08:43

%S 2,2,4,2,3,6,2,3,4,8,2,3,4,6,10,2,3,4,5,8,12,2,3,4,5,6,9,14,2,3,4,5,6,

%T 8,10,16,2,3,4,5,6,7,9,12,18,2,3,4,5,6,7,8,10,14,20,2,3,4,5,6,7,8,9,

%U 12,15,22,2,3,4,5,6,7,8,9,10,14,16,24,2,3,4,5,6,7,8,9,10,12,15,18,26,2,3,4,5

%N Array read by antidiagonals: Row n contains the positive multiples of the first n primes.

%e Row 2 consists of the positive multiples of the first 2 primes (2 and 3). 2,3,4,6,8,9,10,12,14,15,16,18,20,...

%e From _R. J. Mathar_, Jul 04 2009: (Start)

%e The table starts

%e 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40

%e 2 3 4 6 8 9 10 12 14 15 16 18 20 21 22 24 26 27 28 30

%e 2 3 4 5 6 8 9 10 12 14 15 16 18 20 21 22 24 25 26 27

%e 2 3 4 5 6 7 8 9 10 12 14 15 16 18 20 21 22 24 25 26

%e 2 3 4 5 6 7 8 9 10 11 12 14 15 16 18 20 21 22 24 25

%e 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 18 20 21 22 24

%e 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 20 21 22

%e 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21

%e (End)

%p T := proc(n,k) option remember; local i,a; if k = 1 then 2; else for a from procname(n,k-1) +1 do for i from 1 to n do if a mod ithprime(i) =0 then RETURN(a); fi; od: od: fi; end: for d from 1 to 15 do for k from 1 to d do printf("%d,",T(d-k+1,k)) ; od: od: # _R. J. Mathar_, Jul 04 2009

%K nonn,tabl

%O 1,1

%A _Leroy Quet_, Jun 13 2009

%E More terms from _R. J. Mathar_, Jul 04 2009