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A124064 Table read by rows: T(d,k) (d >= 1, k >= 1) = smallest prime p of k (not necessarily consecutive) primes in arithmetic progression with common difference d. 4
2, 2, 2, 3, 3, 2, 2, 2, 3, 3, 2, 2, 2, 5, 5, 5, 5, 2, 2, 3, 3, 2, 2, 2, 3, 3, 2, 2, 2, 5, 5, 5, 5, 2, 2, 3, 3, 2, 2, 2, 3, 2, 2, 2, 5, 5, 5, 2, 2, 3, 3, 2, 2, 2, 7, 2, 2, 5, 5, 59, 2, 2, 3, 2, 2, 2, 3, 3, 2, 2, 2, 7, 7, 7, 7, 7, 2, 2, 5, 2, 2, 3, 3, 2, 2, 2, 5, 7, 31, 2, 2, 3, 3, 2, 2, 2, 3, 3, 2, 2, 2, 5, 5, 5, 5 (list; graph; refs; listen; history; internal format)
OFFSET

1,1

LINKS

R. J. Mathar, Table for d <= 1000 (PDF)

FORMULA

T(n,1) = 2.

lim n->inf (a(n)/n) = SUM(p prime; (p-1)/(#(p-1)) = 2.92005097731613471209+

EXAMPLE

Table begins:

d \k|..1..2..3..4..5..

----+-----------------

..1.|..2..2

..2.|..2..3..3

..3.|..2..2

..4.|..2..3..3

..5.|..2..2

..6.|..2..5..5..5..5

..7.|..2

..8.|..2..3..3

..9.|..2..2

.10.|..2..3..3

.11.|..2..2

.12.|..2..5..5..5..5

.13.|..2

.14.|..2..3..3

.15.|..2..2

.16.|..2..3

.17.|..2..2

.18.|..2..5..5..5

.19.|..2

.20.|..2..3..3

T(24,4) = 59 since (59,83,107,131) is the first A.P. of 4 primes with difference 24.

CROSSREFS

Assuming the k-tuples conjecture, A123556 gives lengths of table rows.

Sequence in context: A081414 A094321 A107789 * A096916 A098014 A059957

Adjacent sequences:  A124061 A124062 A124063 * A124065 A124066 A124067

KEYWORD

nonn,tabf

AUTHOR

R. J. Mathar (mathar(AT)strw.leidenuniv.nl), Nov 04 2006

EXTENSIONS

Edited by David W. Wilson, Nov 05 2006 and Nov 25 2006

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Last modified February 15 05:45 EST 2012. Contains 205694 sequences.