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A117531 Number of primes in the n-th row of the triangle in A117530. 5
1, 2, 3, 3, 5, 3, 7, 3, 5, 6, 6, 6, 13, 3, 11, 8, 12, 8, 13, 10, 8, 7, 12, 10, 9, 21, 6, 22, 11, 7, 13, 12, 21, 13, 14, 16, 18, 7, 20, 17, 21, 20, 24, 14, 18, 20, 16, 16, 35, 10, 18, 29, 18, 30, 30, 26, 21, 18, 21, 29, 16, 22, 32, 40, 10, 27, 24, 25, 45, 18, 39, 40, 43, 11, 11 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

1 <= a(n) <= n; conjecture: a(n) < n for n>13.

LINKS

Table of n, a(n) for n=1..75.

FORMULA

a(n) = Sum(A010051(A117530(n,k)): 1 <= k <= n).

CROSSREFS

Sequence in context: A140187 A214127 A111607 * A275940 A105555 A066858

Adjacent sequences:  A117528 A117529 A117530 * A117532 A117533 A117534

KEYWORD

nonn

AUTHOR

Reinhard Zumkeller, Mar 25 2006

STATUS

approved

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Last modified February 16 03:36 EST 2019. Contains 320140 sequences. (Running on oeis4.)