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A109026 6-almost primes (A046306) whose digit reversal is different and also has 6 prime factors (with multiplicity). "Emirp Tsolma-6.". 7
2576, 2970, 4284, 4356, 4410, 4600, 4698, 4824, 5265, 5625, 6534, 6752, 6900, 8250, 8964, 10710, 10890, 13140, 13986, 16236, 16335, 17577, 18504, 19494, 20286, 20574, 21114, 21150, 21160, 21336, 21492, 21576, 21609, 21900, 21996, 22392, 22770 (list; graph; refs; listen; history; internal format)
OFFSET

1,1

COMMENTS

This sequence is the k = 6 instance of the series which begins with k = 1 (emirps), k = 2 (emirpimes), k = 3 (emirp tsolma-3 = A109023), k = 4 (emirp tsolma-4 = A109024), k = 5 (emirp tsolma-5 = A109025).

The Mathematica code for this was written by Ray Chandler who extended this sequence. He also has more values.

REFERENCES

Jonathan Vos Post, "1066 and All That: Emirp Tsolma-3 and Related Integer Sequences." Forthcoming paper on this sequence.

LINKS

Eric Weisstein's World of Mathematics, Almost Prime.

Eric Weisstein's World of Mathematics, Emirp.

Eric Weisstein and Jonathan Vos Post, Emirpimes.

EXAMPLE

a(1) = 2576 is in this sequence because 2576 = 2^4 * 7 * 23 is a 6-almost prime and reverse(2576) = 6752 = 2^5 * 211 is also a 6-almost prime.

CROSSREFS

Cf. A046306, A006567, A097393, A109018, A109023-A109025, A109027-A109131.

Sequence in context: A175016 A031789 A001294 * A034415 A201510 A171257

Adjacent sequences:  A109023 A109024 A109025 * A109027 A109028 A109029

KEYWORD

nonn,base

AUTHOR

Jonathan Vos Post (jvospost3(AT)gmail.com), Jun 16 2005

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Last modified February 17 14:50 EST 2012. Contains 206050 sequences.