A317743 Valleys in A064800: terms which are smaller than their neighbors.

14, 18, 20, 27, 30, 32, 35, 38, 42, 44, 51, 54, 57, 59, 62, 67, 68, 72, 74, 80, 87, 90, 93, 98, 102, 104, 110, 114, 123, 128, 131, 132, 135, 138, 140, 143, 147, 150, 152, 158, 163, 164, 171, 174, 179, 182, 187, 192, 194, 198, 200

Offset: 1

Author

Zak Seidov, Aug 05 2018

Keywords

• nonn

Comments

From Zak Seidov, Sep 21 2018: (Start)

First second-order valley is a(514) = 516

with {521, 517, 516, 517, 520}.

First third-order valley is a(k=265827) = 265829

with {265833, 265831, 265830, 265829, 265831, 265832, 265834}.

Are there minima of higher order? (End)

Examples

			a(1) = 14 is the first valley (local minimum) in A064800 as A064800(13) = 14 is less than A064800(12) = 15 and A064800(14) = 16.
		

Crossrefs

Cf. A064800, A319504.

Programs

Mathematica

Transpose[ Select[ Partition[(# + PrimeOmega[#]) & /@ Range[201], 3, 1], #[[1]] > #[[2]] < #[[3]] &]][[2]] (* Giovanni Resta, Aug 09 2018 *)

PARI

lista(nn) = {my(v = vector(nn, n, n + bigomega(n))); for (n=2, nn, if ((v[n] < v[n-1]) && (v[n] < v[n+1]), print1(v[n], ", ")););} \\ Michel Marcus, Sep 07 2018