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A185271
Differences between consecutive norms of Gaussian primes.
1
3, 4, 4, 4, 12, 8, 4, 8, 4, 8, 12, 16, 8, 4, 8, 4, 8, 16, 12, 8, 16, 8, 12, 4, 32, 4, 8, 16, 12, 8, 4, 12, 20, 4, 20, 12, 4, 8, 12, 16, 8, 4, 8, 12, 12, 16, 8, 4, 48, 12, 8, 12, 16, 12, 8, 16, 8, 12, 4, 24, 12, 8, 12, 4, 24, 8, 24, 24, 4, 8, 4, 24, 12, 12, 8
OFFSET
1,1
COMMENTS
If this sequence goes to infinity fast enough then the Gaussian moat-crossing problem is solved and it is impossible to walk to infinity in the complex plane using steps of bounded length stepping only on Gaussian primes.
FORMULA
a(n) = A055025(n+1) - A055025(n).
EXAMPLE
The first Gaussian prime (restricting ourselves to the first octant) is 1+i which has norm 2 (1^2+1^2). The second is 2+i with norm 5 (2^2+1^2). The difference in those norms is 3, the first term in this sequence.
CROSSREFS
Cf. A055025 (norms of Gaussian primes).
Sequence in context: A058559 A232092 A345196 * A352285 A158012 A032446
KEYWORD
nonn,easy
AUTHOR
Patrick P Sheehan, Jan 25 2012
STATUS
approved