On Sat, 2 Jan 1999, Don McDonald wrote:
> Alan Robert BOYD
> number theorist
> d. Hamilton N.Z. 1.1.1 999,
> aged 47 years.
> The most prolific mathematician of the
> 20th century, Paul Erdos, described
> the mathematician species as a device
> for turning coffee into theorems.
> Judging by the cup stains on Alan Boyd's
> letters to me, Alan, who died this year, practised a lot of
> number theory. Just before Christmas 1998
> Alan requested a disk of Acorn computer
> programs from me; he wanted to hire a
> computer. Although I did a few short
> calculations for Alan, he usually produced
> his own printouts, photocopying one side
> of the paper and copying dozens of columns of figures
> by hand in pen or pencil on the reverse side.
> He was the human printer computer.
> Alan studied sequences of integers.
> Hati numbers are integers
> 2^a .3^ b.N
> where a+b is even, and N is a whole number
> not divisible by 2 or 3.
> A few Hati numbers are
> 1 = 2^0 .3^0 a+b= 0
> 4 = 2^2 a+b = 2
> 6 = 2^1 .3^1 a+b= 2
> 9= 3^ 2 a+b= 2
> and 20 = 2^2 .5. a+b= 2.
> On my kitchen wall Alan gave me a colour
> coded array of Hati nos. up to 100.
> Alan taught me about Panarithmic numbers
> and Boyd numbers and I introduced him to
> primitive roots. He gave me a program.
> Can you do this
> program on your computer? I could.
> Alan arrived on the doorstep of my
> Newtown, Wellington, bedsit flat from Dunedin.
> He may have seen my ads in nz science mthly
> magaz. and was referred to me by
> the maths dept at Canterbury University.
> Every year he travelled to the North
> Island for NZ Scrabble championships.
> And he visited contacts in Wellington,
> including a brother in Lower Hutt and
> Later he moved to Hamilton. Another
> habit that Alan briefly pursued was
> mailing press cuttings about bizarre incidents
> or Court proceedings. His research was
> published rarely in NZ mathematics magazine.
> Alan was the first pedestrian killed on
> NZ roads in 1 January 1999. A Z (alpha and
> omega.) It is presumed that he was the
> victim of a hit-and-run driver.
> DON S McDonald
> 63/5 hut chi son rd
> newtown wellington. 2
> new zealand
> call minder 64 (4) 389 6820.
> date: 27.12.98 15:33 nzdt.
> subject: nextprime bin(300,150)+185.
> ng: sci.math reference, finding large prime nos.
> PRIME p divides bin(2n,n) + mp
> IFF there exists any k >=0
> such that Floor(2n/p^k) = Odd.
> Whence, nextprime = 2^300/root(150pi)
> = bin(300,150) +185 = 9.384E88
> contains no prime factor < 300.
> bin = nCr = n! / r!(n-r)!
> power of
> .. in 300! 150!
> 2 150
> 4 75 37
> 3 100
> 9 33 16
> 5 60
> 25 12
> 125 2
> 7 42
> 49 6
> 37 8
> / don.
> (644 welgtn n. zeal) 389-6820.