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A176363 Non-semiprime numbers of order 2. 2
1, 2, 3, 7, 11, 12, 17, 18, 19, 24, 27, 28, 29, 30, 36, 37, 42, 43, 44, 45, 47, 48, 54, 56, 61, 63, 64, 66, 67, 68, 71, 72, 75, 78, 79, 80, 83, 89, 90, 92, 97, 98, 100, 101, 102, 104, 105, 107, 108, 110, 112, 114, 116, 117, 120, 125, 126, 131, 132, 135, 137, 144, 147, 148 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Non-semiprimes with non-semiprime subscripts (or indices).

LINKS

Table of n, a(n) for n=1..64.

FORMULA

a(n) = A100959(A100959(n)).

MAPLE

A100959 := proc(n) option remember; if n = 1 then 1; else for a from procname(n-1)+1 do if numtheory[bigomega](a) <> 2 then return a; end if; end do end if; end proc: A176363 := proc(n) A100959(A100959(n)) ; end proc: seq(A176363(n), n=1..80) ; # R. J. Mathar, Apr 25 2010

CROSSREFS

Sequence in context: A064956 A110449 A229082 * A067991 A114600 A088905

Adjacent sequences:  A176360 A176361 A176362 * A176364 A176365 A176366

KEYWORD

nonn

AUTHOR

Juri-Stepan Gerasimov, Apr 16 2010

EXTENSIONS

Corrected (66 inserted) R. J. Mathar, Apr 25 2010

STATUS

approved

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Last modified September 25 21:48 EDT 2020. Contains 337344 sequences. (Running on oeis4.)