A083415 Triangle read by rows: T(n,k) is defined as follows. Write the numbers from 1 to n^2 consecutively in n rows of length n; T(n,k) = number of primes in k-th row.
0, 1, 1, 2, 1, 1, 2, 2, 1, 1, 3, 1, 2, 2, 1, 3, 2, 2, 2, 1, 1, 4, 2, 2, 1, 2, 2, 2, 4, 2, 3, 2, 1, 3, 1, 2, 4, 3, 2, 2, 3, 2, 2, 2, 2, 4, 4, 2, 2, 3, 2, 2, 3, 2, 1, 5, 3, 3, 3, 2, 2, 3, 2, 2, 4, 1, 5, 4, 2, 4, 2, 3, 3, 1, 4, 2, 2, 2, 6, 3, 3, 3, 3, 3, 3, 3, 3, 1, 3, 2, 3, 6, 3, 4, 3, 3, 4, 2, 4
Offset: 1
Examples
{0} {1, 1} {2, 1, 1} from / 1 2 3 / 4 5 6 / 7 8 9 / {2, 2, 1, 1} {3, 1, 2, 2, 1} {3, 2, 2, 2, 1, 1}
References
- Paulo Ribenboim, "The Little Book Of Big Primes," Springer-Verlag, NY 1991, page 185.
Links
- T. D. Noe, Rows n=1..100 of triangle, flattened
Programs
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Haskell
a083415 n k = a083415_row n !! (k-1) a083415_row n = f n a010051_list where f 0 _ = [] f k chips = (sum chin) : f (k - 1) chips' where (chin,chips') = splitAt n chips a083415_tabl = map a083415_row [1..] -- Reinhard Zumkeller, Jun 10 2012
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Mathematica
Table[PrimePi[m n]-PrimePi[(m-1) n], {n, 17}, {m, n}]
Comments