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 A244253 a(n) = the frequency of the most common final digit of a prime with n digits. 0
 1, 6, 40, 268, 2103, 17623, 146590, 1274284, 11272025, 101053126, 915755611, 8372478663, 77114448042, 714719245204 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS For the most common final digit, see A244189. LINKS EXAMPLE Of the 3-digit primes, there are 35 that end in 1, 35 that end in 3, 40 that end in 7, and 33 that end in 9. Thus since 7 has the most, a(3) = 40. PROG (Python) import sympy from sympy import isprime def end1(d, n): ..lst = [] ..for k in range(10**(d-1), 10**d): ....num = '' ....count = 0 ....for i in range(10**(n-d-1), 10**(n-d)): ......if isprime(int(str(i)+str(k))): ........count += 1 ....lst.append(count) ..return max(lst) n = 2 while n < 10: ..print(end1(1, n), end=', ') ..n += 1 CROSSREFS Cf. A244189. Sequence in context: A135032 A122074 A289208 * A123357 A081016 A083426 Adjacent sequences:  A244250 A244251 A244252 * A244254 A244255 A244256 KEYWORD nonn,base,more,hard AUTHOR Derek Orr, Jun 24 2014 EXTENSIONS a(8)-a(14) from Hiroaki Yamanouchi, Jul 10 2014 STATUS approved

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Last modified October 19 16:17 EDT 2019. Contains 328223 sequences. (Running on oeis4.)