Find all possible triplets a,b,c that appear as adjacent coefficents in the same row of Pascal triangle and form an arithmetic sequence.

(In reply to possible solution by Dej Mar)

I suspect that Dej Mar may have done much as I.

I set up an Excel spreadsheet to generate down to about 20 rows.
The cells in intermediate rows reported the difference between two neighbouring cells in the row above.

Other than at the "apex" of rows, the only time when two differences were the same were as indicated by Dej Mar.

Posted by brianjn on 2011-07-14 00:39:20