|
| |
|
|
A116054
|
|
n times pi(n) is a palindrome, where pi(n) = PrimePi(n) = A000720(n).
|
|
1
|
|
|
|
1, 2, 3, 4, 11, 28, 33, 37, 44, 53, 132, 138, 279, 378, 458, 474, 482, 504, 674, 1628, 1696, 2002, 2332, 3117, 4183, 5518, 6341, 6623, 7094, 19261, 25971, 28402, 28831, 33827, 39119, 51387, 65621, 85997, 87843, 174944, 178926, 212212, 258357
(list;
graph;
refs;
listen;
history;
text;
internal format)
|
|
|
|
OFFSET
|
1,2
|
|
|
LINKS
|
Chai Wah Wu, Table of n, a(n) for n = 1..100
|
|
|
EXAMPLE
|
85997 * p(85997) = 719020917.
|
|
|
MATHEMATICA
|
ntpQ[n_]:=Module[{idn=IntegerDigits[n*PrimePi[n]]}, idn==Reverse[idn]]; Select[Range[300000], ntpQ] (* Harvey P. Dale, Nov 13 2013 *)
|
|
|
PROG
|
(Python)
from sympy import nextprime
n, k, m, A116054_list = 0, 1, 2, []
while len(A116054_list) < 100:
for i in range(k, m):
s = str(i*n)
if s == s[::-1]:
A116054_list.append(i)
n += 1
k, m = m, nextprime(m) # Chai Wah Wu, Jul 25 2018
|
|
|
CROSSREFS
|
Cf. A000720, A116053.
Sequence in context: A037432 A301877 A221172 * A339782 A176621 A099527
Adjacent sequences: A116051 A116052 A116053 * A116055 A116056 A116057
|
|
|
KEYWORD
|
nonn,base
|
|
|
AUTHOR
|
Giovanni Resta, Feb 13 2006
|
|
|
STATUS
|
approved
|
| |
|
|
