A084726 Smallest common difference of the arithmetic progression of length n, beginning with 1 whose product of first n terms + 1 is a prime.
1, 1, 1, 3, 7, 5, 5, 5, 7, 7, 1, 7, 11, 3, 41, 15, 21, 25, 11, 3, 69, 5, 87, 35, 17, 27, 1, 27, 5, 9, 3, 53, 9, 21, 25, 9, 1, 57, 15, 19, 1, 21, 191, 19, 25, 149, 83, 23, 7, 121, 205, 133, 185, 39, 43, 23, 9, 9, 3, 257, 109, 25, 107, 65, 19, 43, 97, 115, 197, 89, 109, 55, 1, 161, 61
Offset: 1
Keywords
Examples
The arithmetic progression in triangular form: 1 1 2 1 2 3 1 4 7 10 1 8 15 22 29 1 6 11 16 21 26 ...
Crossrefs
Cf. A084727.
Extensions
More terms from David Wasserman, Jan 03 2005
Example triangle corrected by Nathaniel Johnston, Jun 25 2011
Comments