OK - Ian wondered about automating a search in OEIS.
With a little inspection of the "page source" I've come up with this
script; it seems to work!
Although lots of OEIS lists are potentially mentioned if a series is
matched, many are cross-references
rather than the lower number of series that actually match.
My research has hardly been far-reaching, so there may well turn out to
be exceptions to this rule, but
so far it appears that the pattern
'<a href="/Axxxxxx/list">'
works for the headwords, as a dictionary might describe these references.
=============================================================
load '~addons/web/gethttp/gethttp.ijs'
goeis =: getoeisseries =: {{
commas =. {{ NB. form a comma-separated list suitable for an OEIS
search
q =. 1|.' '-.~,','&,@:":"0 y
if. # imin=. I. q = '_' do.
q =. '-' imin } q
end.
}}
NB. commas 10?10
NB. 6,1,9,0,8,2,4,7,3,5,
OEIS =. 'http://oeis.org/search?q='
NB. read RAW; the result of searching in OEIS for commas y
NB. Using global RAW for later inspection by user
RAW =: gethttp OEIS,commas y
NB. find all occurrences of '<a href="/A,d' for digit characters 0-9
ix =. 0 -.~ , {{ y&{{ x I.@:E.~ '<a href="/A',y }} "0 '0123456789'
}} RAW
NB. looking for subset matching "/Axxxxxx/list">
ix =. ix +/ 7 + 10 + i.7
if. +/ ok =. '/list">' -:"1 ix {"1 RAW do.
echo '3 results found'
RAW {~ _7 + ok#ix
else.
echo 'Sorry, but the terms do not match anything in the table.'
RAW =: ''
end.
}}
NB. goeis 5 9 15 23 33 45 59
NB. 3 results found
NB. A027688
NB. A118403
NB. A134586
NB. goeis 5 9 15 23 33 45 59 27
NB. Sorry, but the terms do not match anything in the table.
===============================================================================
IF the series is found, you can go on to examine - even parse?! - the
global "RAW" -
though I expect it's just as useful to go to the browser. I don't use
JHS enough to know
how to integrate this approach in that enviornment.
Mike
On 06/03/2022 14:06, 'Michael Day' via Programming wrote:
I don't yet see how to separate the series itself/themselves from
cross-refs!
M
On 06/03/2022 12:18, 'Michael Day' via Programming wrote:
Late to the power party!
This is one way to automate the OEIS look-up - I'm not an expert on
parsing the result, but hunting for 'A', a single digit seems
a good starter:
OEIS =: 'http://oeis.org/search?q=' NB. fails with https://... !
getoeisseries =:{{ {{(-.{.) ' ',,/ y&{{~.x{~(i.7)+/~ x I.@:E.~
'A',y}}"0 '0123456789' }} RAW=:gethttp OEIS,commas y}}
getoeisseries 5 9 15 23 33 45 59
A027688
A002522
A007954
A176271
A118403
A118401
A118400
A118407
A118402
A134586
where commas is what I always use to format series for OEIS searches:
commas =: 3 : 0 NB. crude - I forget how to format negatives using
- with some ": variant!!!
q =. 1|.' '-.~,','&,@:":"0 y
if. # imin=. I. q = '_' do.
q =. '-' imin } q
end.
)
Not a primitive adverb, but it's my starter for 10,
Mike
On 06/03/2022 06:36, Ian Clark wrote:
Let's cheat and look it up in oeis.org …
Skip's sequence is A027688, dropping the first term
A027688 is defined as: (n^2 + n + 3)
but (n*n + n + 3) gives better results with (13 :)
q=: 13 : '(y*y) + y + 3'
q
*~ + 3 + ]
q >:i.10
5 9 15 23 33 45 59 75 93 113
Has anyone tried automating OEIS lookup? It could be the basis for a
nifty
new primitive adverb: (...) as in:
5 9 15 23 33 ...
[NB NB NB snipped earlier posts! MD]
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