Pascal's triangle

[roadrunner]

Function pascal(x) returns a level of Pascal's triangle.

Example:

pascal(7) returns {1,7,21,35,35,21,7,1}
the 7th level of Pascal's triangle

Code:

#pragma mode(separator(.,;) integer(h32))

EXPORT pascal(x)
BEGIN
 case
  if x < 1 then {1};end;
  if x < 2 then {1,1}; end;
 default
  concat(1,execon("&1+&2",pascal(x−1)),1);
 end;
END;

[Gerald H]

Isn't {1,7,21,35,35,21,7,1} the 8th line?

[roadrunner]

(09-01-2015 04:30 PM)Gerald H Wrote:  Isn't {1,7,21,35,35,21,7,1} the 8th line?

Here: http://ptri1.tripod.com/ they start counting with row zero, making {1,7,21,35,35,21,7,1} row 7. But Blaise Pascal himself, it seems, would have agreed with you: https://en.wikipedia.org/wiki/Pascal%27s...Pascal.jpg

-road

[Joe Horn]

Alternative method, using a single expression:
pcoeff(makemat(-1,j,1)) --> jth row of Pascal's Triangle
Works both in Home and CAS.