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A116202
Numbers k such that k concatenated with k+6 gives the product of two numbers which differ by 8.
6
7, 54, 234, 267, 894, 58227, 7962242238271227055830015496107, 60153956829051761181170060654114714579377214308482459, 2019668016997743800626449453386765007975459365956534868322001037107, 3031524678136833532602149525055953135725227119574025423809994922862
OFFSET
1,1
LINKS
EXAMPLE
58227//58233 = 76303 * 76311, where // denotes concatenation.
PROG
(Python)
from itertools import count, islice
from sympy import sqrt_mod
def A116202_gen(): # generator of terms
for j in count(0):
b = 10**j
a = b*10+1
for k in sorted(sqrt_mod(22, a, all_roots=True)):
if a*(b-6) <= k**2-22 < a*(a-7) and k>4:
yield (k**2-22)//a
A116202_list = list(islice(A116202_gen(), 7)) # Chai Wah Wu, Feb 21 2024
CROSSREFS
KEYWORD
nonn,base
AUTHOR
Giovanni Resta, Feb 06 2006
EXTENSIONS
a(8)-a(10) from Chai Wah Wu, Feb 21 2024
STATUS
approved