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%I #22 Mar 16 2019 12:09:46
%S 2,3,6,5,15,30,7,35,105,210,11,77,385,1155,2310,13,143,1001,5005,
%T 15015,30030,17,221,2431,17017,85085,255255,510510,19,323,4199,46189,
%U 323323,1616615,4849845,9699690,23,437,7429,96577,1062347,7436429,37182145,111546435,223092870
%N Triangle read by rows in which the k-th term in row n (n >= 1, k = 1..n) is Product_{i=0..k-1} prime(n-i).
%C Also, square array A(m,n) in which row m lists all products of m consecutive primes (read by falling antidiagonals). See also A248164. - _M. F. Hasler_, May 03 2017
%H Reinhard Zumkeller, <a href="/A098012/b098012.txt">Rows n = 1..125 of triangle, flattened</a>
%F n-th row = partial products of row n in A104887. - _Reinhard Zumkeller_, Oct 02 2014
%e 2
%e 3 3*2
%e 5 5*3 5*3*2
%e 7 7*5 7*5*3 7*5*3*2
%e Or, as an infinite square array:
%e 2 3 5 7 ... : row 1 = A000040,
%e 6 15 35 77 ... : row 2 = A006094,
%e 30 105 385 1001 ... : row 3 = A046301,
%e 210 1155 5005 17017 ... : row 4 = A046302,
%e ..., with col.1 = A002110, col.2 = A070826, col.3 = A059865\{1}. - _M. F. Hasler_, May 03 2017
%p T:=(n,k)->mul(ithprime(n-i),i=0..k-1): seq(seq(T(n,k),k=1..n),n=1..9); # _Muniru A Asiru_, Mar 16 2019
%t Flatten[ Table[ Product[ Prime[i], {i, n, j, -1}], {n, 9}, {j, n, 1, -1}]] (* _Robert G. Wilson v_, Sep 21 2004 *)
%o (Haskell)
%o a098012 n k = a098012_tabl !! (n-1) !! (k-1)
%o a098012_row n = a098012_tabl !! (n-1)
%o a098012_tabl = map (scanl1 (*)) a104887_tabl
%o -- _Reinhard Zumkeller_, Oct 02 2014
%o (PARI) T098012(n,k)=prod(i=0,k-1,prime(n-i)) \\ "Triangle" variant
%o A098012(m,n)=prod(i=0,m-1,prime(n+i)) \\ "Square array" variant. - _M. F. Hasler_, May 03 2017
%o (GAP) P:=Filtered([1..200],IsPrime);;
%o T:=Flat(List([1..9],n->List([1..n],k->Product([0..k-1],i->P[n-i])))); # _Muniru A Asiru_, Mar 16 2019
%Y Cf. A000040, A002110, A006094, A046301, A046302, A046303.
%Y Cf. A060381 (central terms), A104887, A248147.
%K easy,nonn,tabl
%O 1,1
%A _Alford Arnold_, Sep 09 2004
%E More terms from _Robert G. Wilson v_, Sep 21 2004
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