Nothing Special   »   [go: up one dir, main page]

login

Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 61st year, we have over 378,000 sequences, and we’ve reached 11,000 citations (which often say “discovered thanks to the OEIS”).

A189936
Odd numbers in A076763.
1
105, 165, 195, 255, 273, 315, 345, 357, 385, 399, 465, 483, 525, 555, 585, 627, 663, 693, 705, 735, 765, 777, 795, 897, 915, 957, 975, 1005, 1095, 1113, 1155, 1173, 1185, 1281, 1295, 1305, 1353, 1365, 1515, 1545, 1575, 1617, 1677, 1683, 1725, 1755, 1785, 1815, 1935, 1953
OFFSET
1,1
LINKS
FORMULA
a(n) = A005408(k) = A076763(m).
MAPLE
omega := proc(n) nops( numtheory[factorset](n)) ; end proc:
isA076763 := proc(n) omega(n) > omega(n-1) and omega(n) > omega(n+1) ; end proc:
isA189936 := proc(n) type(n, 'odd') and isA076763(n) ; end proc:
for n from 1 to 2000 by 2 do if isA189936(n) then printf("%d, ", n) ; end if; end do; # R. J. Mathar, May 26 2011
MATHEMATICA
Select[Range[1, 2000, 2], PrimeNu[# - 1] < PrimeNu[#] > PrimeNu[# + 1]&] (* Jean-François Alcover, Nov 14 2016 *)
Select[#[[2, 1]]&/@Select[Partition[Table[{n, PrimeNu[n]}, {n, 2000}], 3, 1], #[[1, 2]] <#[[2, 2]]>#[[3, 2]]&], OddQ] (* Harvey P. Dale, Sep 15 2019 *)
CROSSREFS
KEYWORD
nonn
AUTHOR
EXTENSIONS
Corrected by R. J. Mathar, May 26 2011
STATUS
approved