

A317743


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


1



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
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OFFSET

1,1


COMMENTS

From Zak Seidov, Sep 21 2018: (Start)
First secondorder valley is a(514) = 516
with {521, 517, 516, 517, 520}.
First thirdorder valley is a(k=265827) = 265829
with {265833, 265831, 265830, 265829, 265831, 265832, 265834}.
Are there minima of higher order? (End)


LINKS

Table of n, a(n) for n=1..51.


EXAMPLE

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.


MATHEMATICA

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


PROG

(PARI) lista(nn) = {my(v = vector(nn, n, n + bigomega(n))); for (n=2, nn, if ((v[n] < v[n1]) && (v[n] < v[n+1]), print1(v[n], ", ")); ); } \\ Michel Marcus, Sep 07 2018


CROSSREFS

Cf. A064800, A319504.
Sequence in context: A063828 A060504 A052026 * A118499 A111205 A097324
Adjacent sequences: A317740 A317741 A317742 * A317744 A317745 A317746


KEYWORD

nonn


AUTHOR

Zak Seidov, Aug 05 2018


STATUS

approved



