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A226383 Numbers for which there is at least one 3-smooth representation that is special of level k. 2
5, 7, 11, 19, 19, 23, 29, 31, 35, 37, 47, 49, 53, 65, 65, 67, 73, 79, 85, 85, 89, 89, 97, 101, 103, 119, 121, 121, 125, 131, 133, 143, 143, 149, 151, 157, 161, 169, 175, 179, 185, 185, 197, 205, 211, 211, 215, 221, 223, 227, 233, 239, 251, 259, 259, 259, 269, 271, 275, 277, 283, 287, 287, 289, 313, 313, 319, 323, 323 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,1

COMMENTS

These numbers are of the form 3^k*2^0 + 3^{k-1}*2^{a_1} + ... + 3^1*2^{a_{k-1}} + 3^0*2^{a_k} in which every power 3^i appears, 0 <= i <= k, and where a_i satisfies a_0 = 0, a_0 < a_1 < ... < a_k.

REFERENCES

Kenneth Vollmar, Recursive calculation of 3-smooth representations special of level k, To be submitted mid-2013.

LINKS

Table of n, a(n) for n=0..68.

R. Blecksmith, M. McCallum and J. L. Selfridge, 3-smooth representations of integers, Amer. Math. Monthly, 105 (1998), 529-543.

CROSSREFS

Cf. A213539, A003586.

Sequence in context: A260828 A280651 A089785 * A118386 A240849 A116641

Adjacent sequences:  A226380 A226381 A226382 * A226384 A226385 A226386

KEYWORD

nonn

AUTHOR

Kenneth Vollmar, Jun 05 2013

STATUS

approved

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Last modified May 18 11:30 EDT 2021. Contains 343995 sequences. (Running on oeis4.)