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A180486
Numbers of the form ceiling(A179896(j)/A018252(j)) where A179896(j) mod A018252(j) <> 0.
0
5, 8, 11, 14, 17, 20, 23, 26, 29, 32, 35, 38, 41, 44, 47, 50, 53, 56, 59, 62, 65, 68, 71, 74, 77, 80, 83, 86, 89, 92, 95, 98, 101, 104, 107, 110, 113, 116, 119, 122, 125, 128, 131, 134, 137, 140, 143, 146, 149, 152, 155, 158, 161, 164, 167, 170, 173, 176, 179, 182
OFFSET
1,1
COMMENTS
Previous name was "Ceiling(A179896 / n) for n > 0 and remainder <> 0".
FORMULA
Conjectures from Colin Barker, Nov 25 2019: (Start)
G.f.: x*(5 - 2*x) / (1 - x)^2.
a(n) = 2*a(n-1) - a(n-2) for n>2.
a(n) = 2 + 3*n.
(End)
MAPLE
From R. J. Mathar, Sep 19 2010: (Start)
A018252 := proc(n) option remember; if n = 1 then 1; else for a from procname(n-1)+1 do if not isprime(a) then return a; end if; end do; end if; end proc:
A045943 := proc(n) 3*n*(n+1)/2 ; end proc:
A179896 := proc(n) A045943(A018252(n)-1) ; end proc:
for n from 1 to 130 do a := A179896(n) ; c := A018252(n) ; if a mod c <> 0 then printf("%d, ", ceil(a/c)) ; end if; end do: (End)
CROSSREFS
KEYWORD
easy,nonn
AUTHOR
Odimar Fabeny, Sep 07 2010
EXTENSIONS
Previous name replaced (with a Sep 19 2010 comments entry from R. J. Mathar) by Jon E. Schoenfield, Nov 28 2019
STATUS
approved