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A028559
Palindromes of the form k*(k+5).
1
0, 6, 66, 414, 696, 41814, 42224, 666666, 4282824, 4754574, 4881884, 416343614, 630939036, 4159669514, 6817557186, 42877777824, 4163250523614, 4783601063874, 4986733376894, 47431877813474, 6333914444193336, 44653247574235644, 62141509790514126
OFFSET
1,2
LINKS
Lior Manor, Table of n, a(n) for n = 1..33 (terms 1..27 from Michael S. Branicky)
FORMULA
a(n) = A028558(n) * (A028558(n) + 5). - Michael S. Branicky, Jan 30 2022
PROG
(Python)
from itertools import count, islice
def ispal(n): s = str(n); return s == s[::-1]
def agen():
for k in count(0):
if ispal(k*(k+5)):
yield k*(k+5)
print(list(islice(agen(), 20))) # Michael S. Branicky, Jan 30 2022
CROSSREFS
Sequence in context: A185253 A192089 A119073 * A249639 A163699 A062184
KEYWORD
nonn,base
EXTENSIONS
a(21) and beyond from Michael S. Branicky, Jan 30 2022
STATUS
approved