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A188443 Numbers not appearing in A178133, which gives the number of odd semiprimes between consecutive squares. 2
25, 33, 63, 66, 75, 88, 191, 269, 285, 309, 348, 379, 399, 400, 404, 413, 437, 443, 456, 548, 553, 594, 616, 638, 675, 684, 702, 724, 764, 810, 819, 823, 829, 843, 897, 901, 906, 907, 1000, 1031, 1041, 1068, 1075, 1159, 1200, 1230, 1241, 1255, 1279, 1280, 1281, 1300, 1323, 1332 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..54.

MATHEMATICA

lst={}; k=0; s=4; Do[If[OddQ[n]&&Last/@FactorInteger[n]=={1, 1}, If[n<s^2, k++, AppendTo[lst, k]; k=1; s++]], {n, 2*10^8}]; Complement[Range@3000, Union@lst]

CROSSREFS

Cf. A178133.

Sequence in context: A269345 A134099 A129074 * A068411 A020160 A075452

Adjacent sequences:  A188440 A188441 A188442 * A188444 A188445 A188446

KEYWORD

nonn

AUTHOR

Vladimir Joseph Stephan Orlovsky, Apr 20 2011

STATUS

approved

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Last modified May 29 15:34 EDT 2020. Contains 334700 sequences. (Running on oeis4.)