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A253425
Lengths of runs of identical terms in A253415.
2
1, 1, 6, 11, 18, 12, 5, 22, 91, 143, 1, 93, 370, 182, 20, 20, 315, 332, 973, 157, 1223, 1807, 325, 4044, 7412, 11211, 4600, 2176, 14848, 4659, 3123, 10852, 1678, 20862, 3348
OFFSET
1,3
MATHEMATICA
c[_] = 0; c[1] = j = 1; u = 2; s = 3; Most@ Tally[#][[All, -1]] &@ Reap[Do[d = Divisors[s]; k = 1; While[c[d[[k]]] > 0, k++]; Set[k, d[[k]]]; Set[c[k], i]; If[k == u, While[c[u] > 0, u++]]; Sow[u]; j = k; s += k, {i, 2, 2^12}]][[-1, -1]] (* Michael De Vlieger, Jan 23 2022 *)
PROG
(Haskell)
import Data.List (group)
a253425 n = a253425_list !! (n-1)
a253425_list = map length $ group a253415_list
(Python)
from itertools import islice
from sympy import divisors
def A253425_gen(): # generator of terms
bset, l, m, s = {1}, 0, 2, 3
while True:
for d in divisors(s):
if d not in bset:
bset.add(d)
if m in bset:
yield l
l = 1
while m in bset:
m += 1
else:
l += 1
s += d
break
A253425_list = list(islice(A253425_gen(), 20)) # Chai Wah Wu, Jan 25 2022
CROSSREFS
Sequence in context: A271987 A184550 A109330 * A099225 A315555 A315556
KEYWORD
nonn,more
AUTHOR
Reinhard Zumkeller, Dec 31 2014
EXTENSIONS
a(14)-a(35) from Michael De Vlieger, Jan 23 2022
STATUS
approved