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A147764 Elias omega coded prime numbers represented in decimal. 1
8, 12, 84, 92, 236, 244, 2628, 2636, 2652, 2676, 2684, 5524, 5540, 5548, 5564, 5588, 5612, 5620, 11532, 11548, 11556, 11580, 11596, 11620, 11652, 11668, 11676, 11692, 11700, 11716, 11772, 24076, 24100, 24108, 24148, 24156, 24180, 24204, 24220 (list; graph; refs; listen; history; internal format)
OFFSET

1,1

COMMENTS

The sequence in binary begins:

2 1000

3 1100

5 1010100

7 1011100

The final 0 bit represents an exponent of 1.

Because this is a prefix code, there is a one to one mapping between the integers and integers representing their factors, provided that the coded factors and exponents are adequately delimited, such as by inserting additional 0 bits.

For example, 75600 = 2^4 * 3^3 * 5^2 * 7 is representable as 100^101000 110^110 101010^100 101110^0 -> 1001010000110110010101010001011100 = 9946354780 decimal.

This representation is unambiguous because, e.g., the incorrect reading 1001010000110 splits as 100101000 0110 or 100^101000 0^110 -> 2^4 * 1^3, which is clearly wrong.

CROSSREFS

Sequence in context: A038290 A002288 A137232 * A162466 A098664 A180922

Adjacent sequences:  A147761 A147762 A147763 * A147765 A147766 A147767

KEYWORD

base,easy,nonn

AUTHOR

Reikku Kulon (reikku(AT)gmail.com), Nov 11 2008

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Last modified February 16 09:27 EST 2012. Contains 205904 sequences.