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A087312 a(1) = 1; for n > 1, a(n) is the smallest number == -1 (mod a(n-1)), greater than n, with the same prime signature as n. 1
1, 3, 5, 9, 17, 33, 131, 143055667 (list; graph; refs; listen; history; internal format)
OFFSET

1,2

COMMENTS

a(9) does not exist because -1 is not a square mod 143055667. - David Wasserman (wasserma(AT)spawar.navy.mil), May 02 2005

EXAMPLE

a(6) = 33 has the prime signature of 6 and a(4) = 197 has the prime signature of 7 and 197 == -1 (mod 33).

CROSSREFS

Cf. A087311.

Sequence in context: A083318 A127904 A048578 * A099170 A018095 A003217

Adjacent sequences:  A087309 A087310 A087311 * A087313 A087314 A087315

KEYWORD

fini,full,nonn

AUTHOR

Amarnath Murthy (amarnath_murthy(AT)yahoo.com), Sep 02 2003

EXTENSIONS

Corrected and extended by David Wasserman (wasserma(AT)spawar.navy.mil), May 02 2005

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Last modified February 17 02:48 EST 2012. Contains 205978 sequences.