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A038838 Divisible by square of odd prime. 5
9, 18, 25, 27, 36, 45, 49, 50, 54, 63, 72, 75, 81, 90, 98, 99, 100, 108, 117, 121, 125, 126, 135, 144, 147, 150, 153, 162, 169, 171, 175, 180, 189, 196, 198, 200, 207, 216, 225, 234, 242, 243, 245, 250, 252, 261, 270, 275, 279, 288, 289, 294, 297, 300, 306 (list; graph; refs; listen; history; internal format)
OFFSET

1,1

COMMENTS

Condition 1 of Theorem 7.5 (Robinson, 1979) includes: "k is a multiple of a square of an odd prime." - Jonathan Vos Post (jvospost3(AT)gmail.com), Aug 06 2007

Subsequence of A167662. [From Reinhard Zumkeller (reinhard.zumkeller(AT)gmail.com), Nov 08 2009]

REFERENCES

R. M. Robinson, Multiple tiling of n-dimensional space by unit cubes, Math. Z. 166 (1979), 225-264.

Chuanming Zong, What is known about unit cubes, Bull. Amer. Math. Soc. 42 (2005), 181-211; Robinson theorem cited on p. 204.

LINKS

R. Zumkeller, Table of n, a(n) for n = 1..10000 [From Reinhard Zumkeller (reinhard.zumkeller(AT)gmail.com), Nov 08 2009]

Beeler, M., Gosper, R. W. and Schroeppel, R., HAKMEM ITEM 45

FORMULA

{a(n)} = {j such that for some k>1 A001248(k)|j} = {j such that for some k>0 (A065091(k)^2)|j}. - Jonathan Vos Post (jvospost3(AT)gmail.com), Aug 06 2007

A008966(A000265(a(n))) = 0. [From Reinhard Zumkeller (reinhard.zumkeller(AT)gmail.com), Nov 08 2009]

PROG

(PARI) {a(n)= local(m, c); if(n<1, 0, c=0; m=0; while( c<n, m++; if( moebius(m/2^valuation(m, 2))==0, c++)); m)} /* Michael Somos Aug 22 2006 */

CROSSREFS

Cf. A000040, A001248, A065091.

Sequence in context: A015798 A028494 A167663 * A038837 A034046 A069562

Adjacent sequences:  A038835 A038836 A038837 * A038839 A038840 A038841

KEYWORD

nonn

AUTHOR

Dave Wilson

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Last modified February 17 16:00 EST 2012. Contains 206050 sequences.