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A086786
Triangle read by rows: n-th row is the smallest set of n numbers in arithmetic progression with the same prime signature.
8
1, 2, 3, 3, 5, 7, 5, 11, 17, 23, 5, 11, 17, 23, 29, 7, 37, 67, 97, 127, 157, 481, 485, 489, 493, 497, 501, 505, 635, 707, 779, 851, 923, 995, 1067, 1139, 635, 707, 779, 851, 923, 995, 1067, 1139, 1211, 199, 409, 619, 829, 1039, 1249, 1459, 1669, 1879, 2089, 3841
OFFSET
1,2
COMMENTS
In this sequence "smallest" means that the last term of the arithmetic progression is minimized. A113460 minimizes the first term.
EXAMPLE
Triangle begins:
1
2,3
3,5,7
5,11,17,23
5,11,17,23,29
7,37,67,97,127,157
481,485,489,493,497,501,505
635,707,779,851,923,995,1067,1139
635,707,779,851,923,995,1067,1139,1211
199,409,619,829,1039,1249,1459,1669,1879,2089
...
CROSSREFS
A087310 contains the corresponding common differences, A087308 the initial terms, A087309 the final terms.
Row 10 is the same for A113470, A133276, A133277 and listed as A033168.
Sequence in context: A089934 A113460 A113470 * A211890 A231406 A214034
KEYWORD
nonn,tabl
AUTHOR
Amarnath Murthy, Sep 02 2003
EXTENSIONS
Edited and extended by David Wasserman, Jan 08 2006
Further edits by N. J. A. Sloane, Oct 17 2007
STATUS
approved