This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
import Data.List (elemIndex); import Data.Maybe (fromJust) a258330 = (+ 1) . fromJust . (`elemIndex` a258329_list)
a258225 = flip div 3 . a258083
lista(nn) = {v = []; vs = vecsort(v); for (n=1, nn, k=3; pt = 10^(#digits(n)); while (! (((k % pt) == n) && !vecsearch(vs, k)), k+=3); v = concat(v, k); vs = vecsort(v); print1(k/3, ", "););} \\ Michel Marcus, Jun 26 2015
a258334 = flip div 7 . a258217
import Data.List (isPrefixOf, delete)
a258188 n = a258188_list !! (n-1)
a258188_list = f 1 $ tail $ zip
a008589_list $ map (reverse . show) a008589_list where
f x ws = g ws where
g ((u, vs) : uvs) = if isPrefixOf xs vs
then u : f (x + 1) (delete (u, vs) ws) else g uvs
xs = reverse $ show x
a[n_] := a[n] = For[k = 7, True, k = k + 7, If[Divisible[k - n, 10^IntegerLength[n]] && FreeQ[Array[a, n-1], k], Return[k]]]; Array[a, 54] (* Jean-François Alcover, Feb 07 2018 *)
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