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A094486 Primes of form 2^j+223^j. 1
2, 2472973457, 6115597639891380737 (list; graph; refs; listen; history; internal format)
OFFSET

1,1

COMMENTS

Expression 2^j+q^j below q=prime<=prime[130] provided always prime at j=0; or for j=1 if q is a lesser-twin-prime; or more rarely 3 or 4 primes [four ones at q=3,5,17,37,59,137,179,223,461]; never found 5 or more relevant primes and the corresponding exponents proved to be powers of 2. Formal proofs of observations wanted.

EXAMPLE

The relevant exponents are powers of 2: 0,4,8,128

a[4]=2^128+223^128 = a-prime-with-301-decimal-digits = 382844.....1067137.

CROSSREFS

Cf. A082101, A094473-A094485.

Sequence in context: A034251 A170999 A051241 * A109741 A105759 A154422

Adjacent sequences:  A094483 A094484 A094485 * A094487 A094488 A094489

KEYWORD

nonn,bref

AUTHOR

Labos E. (labos(AT)ana.sote.hu), Jun 01 2004

EXTENSIONS

Corrected by T. D. Noe (noe(AT)sspectra.com), Nov 15 2006

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Last modified February 17 05:54 EST 2012. Contains 205985 sequences.