Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 61st year, we have over 378,000 sequences, and we’ve reached 11,000 citations (which often say “discovered thanks to the OEIS”).
%I #22 Dec 15 2017 17:36:33
%S 1,1,2,9,96,25,1800,44100,103219200,3869835264,128000,104976000000,
%T 3071875232563200,7050692013745766400,626913312768,
%U 332150625000000000000,1292730125539029811200
%N Product of nonzero digits in n-th row of Pascal's triangle.
%e a(6) = 25 because the digits in the 5th row of Pascal's triangle are 1,5,(1,0),(1,0),5,1, the product of the nonzero terms is 25. - _Richard M. Green_, Feb 12 2014
%t A086992[n_]:= Times @@ DeleteCases[0]@Flatten@IntegerDigits@Table[Binomial[n, k], {k, 0, n}] (* _JungHwan Min_, Dec 07 2015 *)
%o (PARI) A051801(n)=my(v=select(k->k>1, digits(n))); prod(i=1, #v, v[i])
%o a(n)=prod(k=1,(n-1)\2,A051801(binomial(n,k)))^2*if(n%2,1,A051801(binomial(n,n/2))) \\ _Charles R Greathouse IV_, Dec 08 2015
%Y Cf. A007318, A066600, A086993, A051801.
%K base,easy,nonn
%O 1,3
%A _Jason Earls_, Jul 29 2003