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A207409 Triangular array: T(k,j)=prime(k)(mod prime(j)), 1<=j<k. 4
1, 1, 2, 1, 1, 2, 1, 2, 1, 4, 1, 1, 3, 6, 2, 1, 2, 2, 3, 6, 4, 1, 1, 4, 5, 8, 6, 2, 1, 2, 3, 2, 1, 10, 6, 4, 1, 2, 4, 1, 7, 3, 12, 10, 6, 1, 1, 1, 3, 9, 5, 14, 12, 8, 2, 1, 1, 2, 2, 4, 11, 3, 18, 14, 8, 6, 1, 2, 1, 6, 8, 2, 7, 3, 18, 12, 10, 4, 1, 1, 3, 1, 10, 4, 9, 5, 20, 14, 12, 6, 2, 1 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

1,3

COMMENTS

Top edge:  A001223

Row sums:  A033955

Row maxs:  A039731

LINKS

Robert Israel, Table of n, a(n) for n = 1..10011 (first 141 rows, flattened)

EXAMPLE

Top 7 rows:

1............. 3 mod 2

1 2............5 mod 2, 5 mod 3

1 1 2..........7 mod 2, 7 mod 3, 7 mod 4

1 2 1 4

1 1 3 6 2

1 2 2 3 6 4

1 1 4 5 8 6 2

MAPLE

P := select(isprime, [$1..100]):

seq(seq(P[k] mod P[j], j=1..k-1), k=1..nops(P)); # Robert Israel, May 01 2017

MATHEMATICA

t = Table[Mod[Prime[k + 1], Prime[j]], {k, 1, 15},

{j, 1, k }];

Flatten[t]   (* A207409 as a sequence *)

TableForm[t] (* A207409 as a triangle *)

CROSSREFS

Cf. A000040.

Sequence in context: A134838 A049843 A131374 * A013632 A080121 A122901

Adjacent sequences:  A207406 A207407 A207408 * A207410 A207411 A207412

KEYWORD

nonn,tabl

AUTHOR

Clark Kimberling, Feb 17 2012

STATUS

approved

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Last modified January 23 03:03 EST 2019. Contains 319368 sequences. (Running on oeis4.)