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A094901
Positive integer values of the integer Schwarzian derivatives of the primes.
1
0, 0, 3, 0, 3, 0, 0, 9, 0, 1, 1, 0, 0, 0, 8, 0, 1, 1, 0, 1, 0, 0, 3, 0, 0, 3, 0, 0, 14, 1, 9, 0, 32, 1, 0, 0, 0, 0, 8, 0, 32, 2, 3, 0, 0, 8, 1, 0, 0, 9, 0, 2, 0, 0, 8, 0, 1, 1, 0, 0, 12, 2, 0, 0, 5, 0, 30, 2, 0, 0, 0, 0, 0, 0, 0, 3, 0, 0, 29, 0, 32, 1, 1, 0, 0, 3, 0, 0, 0, 1, 1, 0, 3, 0, 0, 45, 0, 10, 1, 2, 0
OFFSET
4,3
COMMENTS
Negative values of the integer Schwarzian derivatives of Primes are much larger in magnitude than positives values. The significance of this seems to be in its relationship to zeta zeros on the complex plane.
FORMULA
a(n) = Floor[Abs[IntegerSchwarzianDerivative[Prime[n]]]]
MATHEMATICA
(* Ulam-Newton integer derivatives: *) f1[n_]=Prime[n]-Prime[n-1] f2[n_]=Prime[n]-2*Prime[n-1]+Prime[n-2] f3[n_]=Prime[n]-3*Prime[n-1]+3*Prime[n-2]-Prime[n-3] (* Integer Schwarzian derivative:*) sf[n_]=f3[n]/f1[n]-1.5*(f2[n]/f1[n])^2 af=Table[sf[n], {n, 4, 204}] a=Floor[Abs[af]]
CROSSREFS
Sequence in context: A165951 A300288 A340555 * A030220 A219240 A349612
KEYWORD
nonn
AUTHOR
Roger L. Bagula, Jun 15 2004
STATUS
approved