[seqfan] Observation on A008328 and A205901

Jeremy Gardiner jeremy.gardiner at btinternet.com
Fri Jan 12 22:46:23 CET 2018


It appears that run lengths of zeros in the parity of A008328 gives A205901.

Checked for the 10,000 terms of A008328  given in the b-file.

Parity of A008328
(Number of divisors of p-1, p prime):

1,0,1,0,0,0,1,0,0,0,0,1,0,0,0,0,0,0,0,0,0,0,0,0,0,1,0,0,0,0,0,0,0,0,0,0,0,0,
0,0,0,0,0,0,1,0,0,0,0,0,0,0,0,0,1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
0,0,1,0,0,0,0,...

A205901
(Number of primes between two consecutive primes of the form n^2 + 1):

1, 3, 4, 13, 18, 9, 23, ...

Jeremy Gardiner




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