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A036261
Triangle of numbers arising from Gilbreath's conjecture: successive absolute differences of primes (read by antidiagonals upwards, omitting the initial row of primes).
13
1, 1, 2, 1, 0, 2, 1, 2, 2, 4, 1, 2, 0, 2, 2, 1, 2, 0, 0, 2, 4, 1, 2, 0, 0, 0, 2, 2, 1, 2, 0, 0, 0, 0, 2, 4, 1, 2, 0, 0, 0, 0, 0, 2, 6, 1, 0, 2, 2, 2, 2, 2, 2, 4, 2, 1, 0, 0, 2, 0, 2, 0, 2, 0, 4, 6, 1, 0, 0, 0, 2, 2, 0, 0, 2, 2, 2, 4, 1, 0, 0, 0, 0, 2, 0, 0, 0, 2, 0, 2, 2, 1, 0, 0, 0, 0, 0, 2, 2, 2, 2, 0, 0, 2, 4
OFFSET
1,3
COMMENTS
A variant of A036262, which is the main entry for this array.
REFERENCES
R. K. Guy, Unsolved Problems Number Theory, A10.
C. A. Pickover, The Math Book, Sterling, NY, 2009; see p. 410.
EXAMPLE
Table begins (conjecture is leading term is always 1):
2 3 5 7 11 13 17 19 23 ...
1 2 2 4 2 4 2 4 ...
1 0 2 2 2 2 2 ...
1 2 0 0 0, 0 ...
1 2 0 0 0 ...
1 2 0 0 ...
...
MATHEMATICA
max = 15; triangle = Rest[ NestList[ Abs[ Differences[#] ]& , Prime[ Range[max] ], max] ]; Flatten[ Table[ triangle[[n-k+1, k]], {n, 1, max-1}, {k, 1, n}]] (* Jean-François Alcover, Jan 23 2012 *)
CROSSREFS
Sequence in context: A035443 A180430 A246369 * A140575 A091917 A025657
KEYWORD
tabl,easy,nice,nonn
EXTENSIONS
More terms from Naohiro Nomoto, May 22 2001
STATUS
approved