Prime Bell Numbers
The first few Bell numbers that are primes are:
- 2, 5, 877, 27644437, 35742549198872617291353508656626642567, 359334085968622831041960188598043661065388726959079837 (sequence A051131 in OEIS)
corresponding to the indices 2, 3, 7, 13, 42 and 55 (sequence A051130 in OEIS).
The next prime is B2841, which is approximately 9.30740105 × 106538. As of 2006, it is the largest known prime Bell number. Phil Carmody showed it was a probable prime in 2002. After 17 months of computation with Marcel Martin's ECPP program Primo, Ignacio Larrosa Cañestro proved it to be prime in 2004. He ruled out any other possible primes below B6000, later extended to B30447 by Eric Weisstein.
Read more about this topic: Bell Number
Famous quotes containing the words prime, bell and/or numbers:
“Vanessa wanted to be a ballerina. Dad had such hopes for her.... Corin was the academically brilliant one, and a fencer of Olympic standard. Everything was expected of them, and they fulfilled all expectations. But I was the one of whom nothing was expected. I remember a game the three of us played. Vanessa was the President of the United States, Corin was the British Prime Minister—and I was the royal dog.”
—Lynn Redgrave (b. 1943)
“I was thinking of a son.
The womb is not a clock
nor a bell tolling,
but in the eleventh month of its life
I feel the November
of the body as well as of the calendar.”
—Anne Sexton (1928–1974)
“Publishers are notoriously slothful about numbers, unless they’re attached to dollar signs—unlike journalists, quarterbacks, and felony criminal defendents who tend to be keenly aware of numbers at all times.”
—Hunter S. Thompson (b. 1939)