A244192 -id:A244192 - cp's OEIS frontend

A244191 a(n) = most common final digit for a prime < 10^n, or 0 if there is a tie.

0, 3, 7, 3, 7, 3, 3, 7, 3, 3, 7, 7, 3, 3

Offset: 1

Derek Orr, Jun 22 2014

			For all 25 primes < 100 (10^2), we see that the last digit that appears the most is 3. Thus a(2) = 3.

Index entries for sequences related to final digits of numbers

Cf. A007652, A095178, A244192.

import sympy
from sympy import isprime
def prend(d,n):
  lst = []
  for k in range(10**n):
    if isprime(k):
      lst.append((k%10**d))
  new = 0
  newlst = []
  for i in range(10**(d-1),10**d):
    new = lst.count(i)
    newlst.append(new)
  newlst1 = newlst.copy()
  a = max(newlst1)
  newlst1[newlst1.index(a)] = 0
  b = max(newlst1)
  if a == b:
    return 0
  else:
    return newlst.index(max(a,b)) + 10**(d-1)
n = 2
while n < 10:
  print(prend(1,n),end=', ')
  n += 1

a(9)-a(14) from Hiroaki Yamanouchi, Sep 27 2014

A244267 a(n) = the frequency of the most common 2-digit ending of a prime < 10^n.

Original entry on oeis.org

1, 6, 35, 250, 1986, 16716, 144183, 1271765, 11378311, 102956670, 940224567, 8651691637, 80123673992

Offset: 2

Derek Orr, Jun 24 2014

			Of the primes up to and including the last of the 3-digit primes, the most common 2-digit ending occurs 6 times. Thus a(3) = 6.

Cf. A244192.

import sympy
from sympy import isprime
def prend1(d,n):
  lst = [ ]
  for k in range(10**n):
    if isprime(k):
      lst.append((k%10**d))
  new = 0
  newlst = [ ]
  for i in range(10**(d-1),10**d):
    new = lst.count(i)
    newlst.append(new)
  return max(newlst)
n = 3
while n < 10:
  print(prend1(2,n),end=', ')
  n += 1

a(9)-a(12) from Hiroaki Yamanouchi, Aug 26 2014
Example corrected by Harvey P. Dale, Sep 27 2018
a(13)-a(14) from Giovanni Resta, Oct 23 2018

cp's OEIS Frontend

A244191 a(n) = most common final digit for a prime < 10^n, or 0 if there is a tie.

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