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A109028 8-almost primes (A046310) whose digit reversal is different and also has 8 prime factors (with multiplicity). "Emirp Tsolma-8.". 5
16560, 25515, 27864, 42480, 46872, 51552, 57348, 61488, 65448, 67797, 69408, 69840, 79776, 80496, 84375, 84456, 88416, 105336, 119448, 125928, 160416, 167076, 202032, 204984, 206928, 210960, 211104, 211464, 213750, 213792, 213920, 213984 (list; graph; refs; listen; history; internal format)
OFFSET

1,1

COMMENTS

This sequence is the k = 8 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), k = 6 (emirp tsolma-6 = A109026), k = 7 (emirp tsolma-7 = A109027).

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(2) = 25515 is in this sequence because 25515 = 3^6 * 5 * 7 is an 8-almost prime and reverse(25515) = 51552 = 2^5 * 3^2 * 179 is also an 8-almost prime.

CROSSREFS

Cf. A046310, A006567, A097393, A109018, A109023-A109027, A109029-A109131.

Sequence in context: A186848 A170779 A091089 * A183657 A170788 A057329

Adjacent sequences:  A109025 A109026 A109027 * A109029 A109030 A109031

KEYWORD

nonn,base

AUTHOR

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

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Last modified February 16 20:45 EST 2012. Contains 205964 sequences.