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A131749 Triangle of successive absolute differences of semiprimes. +0
1
4, 2, 6, 1, 3, 9, 1, 2, 1, 10, 0, 1, 3, 4, 14, 1, 1, 0, 3, 1, 15, 0, 1, 2, 2, 5, 6, 21, 1, 1, 0, 2, 0, 5, 1, 22, 1, 0, 1, 1, 3, 3, 2, 3, 25, 1, 0, 0, 1, 0, 3, 0, 2, 1, 26, 1, 0, 0, 0, 1, 1, 4, 4, 6, 7, 33, 1, 0, 0, 0, 0, 1, 0, 4, 0, 6, 1, 34, 0, 1, 1, 1, 1, 1, 2, 2, 6, 6, 0, 1, 35 (list; table; graph; listen)
OFFSET

1,1
COMMENT

Semiprime analogue of A036262. The conjecture analogous to Gilbreath's conjecture is that the leading term (after the second row) is always 0 or 1. First diagonal is semiprimes (A001358). Second diagonal is first differences of semiprimes (A065516).

EXAMPLE

Table begins:

4..6..9.10.14.15.21.22.25.26.33.34.35..A001358.

2..3..1..4..1..6..1..3..1..7..1..1.....A065516.

1..2..3..3..5..5..2..2..6..6..0.

1..1..0..2..0..3..0..4..0..6.

0..1..2..2..3..3..4..4..6.

1..1..0..1..0..1..0..2.

0..1..1..1..1..1..2.

1..0..0..0..0..1.

1..0..0..0..1.

1..0..0..1.

1..0..1.

1..1.

0.

CROSSREFS

Cf. A001358, A036262, A065516.

Sequence in context: A141674 A091664 A010317 this_sequence A016515 A011306 A019719

Adjacent sequences: A131746 A131747 A131748 this_sequence A131750 A131751 A131752

KEYWORD

easy,nonn,tabl

AUTHOR

Jonathan Vos Post (jvospost3(AT)gmail.com), Oct 23 2007

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Last modified December 7 08:40 EST 2009. Contains 170430 sequences.

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