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A109031 11-almost primes (A069272) whose digit reversal is different and also has 11 prime factors (with multiplicity). "Emirp Tsolma-11.". 3
295245, 426816, 542592, 618624, 2112480, 2116224, 2150064, 2154816, 2196000, 2302560, 2327616, 2342277, 2388672, 2555280, 2576896, 2599200, 2768832, 2952288, 2952576, 4017216, 4074240, 4074840, 4076160, 4076568, 4078848 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

This sequence is the k = 11 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), k = 8 (emirp tsolma-8 = A109028), k = 9 (emirp tsolma-9 = A109029), k = 10 (emirp tsolma-10 = A109030).

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

Table of n, a(n) for n=1..25.

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) = 295245 is in this sequence because 295245 = 3^10 * 5 is an 11-almost prime and reverse(295245) = 542592 = 2^7 * 3^3 * 157 is also an 11-almost prime.

CROSSREFS

Cf. A069272, A006567, A097393, A109018, A109023-A109030.

Sequence in context: A258534 A258527 A254919 * A137817 A137818 A303357

Adjacent sequences:  A109028 A109029 A109030 * A109032 A109033 A109034

KEYWORD

nonn,base

AUTHOR

Jonathan Vos Post, Jun 16 2005

EXTENSIONS

a(5)-a(25) from Donovan Johnson, Apr 09 2010

STATUS

approved

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Last modified October 21 05:28 EDT 2021. Contains 348141 sequences. (Running on oeis4.)