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A176347 n-th semiprime minus sum of its prime factors. 1
0, 1, 3, 3, 5, 7, 11, 9, 15, 11, 19, 15, 23, 17, 23, 21, 35, 31, 39, 35, 27, 29, 47, 43, 35, 59, 39, 63, 41, 55, 71, 59, 45, 71, 51, 71, 87, 57, 95, 99, 59, 79, 83, 107, 65, 91, 69, 119, 111, 71, 119, 77, 103, 131, 81, 143, 115, 87, 119, 143, 159, 95, 131, 99, 167, 159, 101 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,3

LINKS

Table of n, a(n) for n=1..67.

FORMULA

a(n) = A001358(n) - A068318(n).

MAPLE

From R. J. Mathar, Apr 20 2010: (Start)

isA001358 := proc(n) numtheory[bigomega](n) = 2 ; end proc:

A001358 := proc(n) option remember ; if n = 1 then return 4 ; else for a from procname(n-1)+1 do if isA001358(a) then return a; end if; end do; end if; end proc:

A084126 := proc(n) min(op(numtheory[factorset](A001358(n)))) ; end proc:

A084127 := proc(n) max(op(numtheory[factorset](A001358(n)))) ; end proc:

A068318 := proc(n) A084126(n)+A084127(n) ; end proc:

A176347 := proc(n) A001358(n)-A068318(n) ; end proc: seq(A176347(n), n=1..80) ; (End)

CROSSREFS

Sequence in context: A176513 A128424 A129758 * A161834 A141867 A163646

Adjacent sequences:  A176344 A176345 A176346 * A176348 A176349 A176350

KEYWORD

nonn

AUTHOR

Juri-Stepan Gerasimov, Apr 15 2010

EXTENSIONS

Entries checked by R. J. Mathar, Apr 20 2010

STATUS

approved

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Last modified September 20 10:51 EDT 2021. Contains 347584 sequences. (Running on oeis4.)