A228628 9's complement of prime(n).

7, 6, 4, 2, 88, 86, 82, 80, 76, 70, 68, 62, 58, 56, 52, 46, 40, 38, 32, 28, 26, 20, 16, 10, 2, 898, 896, 892, 890, 886, 872, 868, 862, 860, 850, 848, 842, 836, 832, 826, 820, 818, 808, 806, 802, 800, 788, 776, 772, 770, 766, 760, 758, 748, 742, 736, 730, 728

Offset

1,1

Comments

a(n) = 10^k - 1 - prime(n) where k is the number of digits in prime(n). If d is d digit in prime(n) replace it with 9 - d.

Links

Charles R Greathouse IV, Table of n, a(n) for n = 1..10000

Formula

a(n) = A061601(A000040(n)). - Charles R Greathouse IV, Aug 29 2013

a(n) = A160668(n) - 1. Alois P. Heinz, Dec 08 2017

Example

a(6) = 86 because prime(6) = 13 and 9 - 1 = 8, 9 - 6 = 3.

Maple

a:= n-> (p-> 10^length(p)-p-1)(ithprime(n)):
seq(a(n), n=1..100);  # Alois P. Heinz, Dec 08 2017

Mathematica

nineComplement[n_] := FromDigits[Table[9, {Length[IntegerDigits[Prime[n]]]}] - IntegerDigits[Prime[n]]]; Table[nineComplement[n], {n, 1, 71}]

Prog

(PARI) a(n)=my(p=prime(n)); 10^#Str(p)-p-1 \\ Charles R Greathouse IV, Aug 29 2013
(Python)
from sympy import primerange
def nc(n): return 10**len(str(n)) - 1 - n
def auptop(limit): return [nc(p) for p in primerange(1, limit+1)]
print(auptop(271)) # Michael S. Branicky, Jul 06 2021

Crossrefs

Cf. A000040, A061601, A160668.

Sequence in context: A021933 A154730 A242967 * A131266 A258094 A258008

Adjacent sequences: A228625 A228626 A228627 * A228629 A228630 A228631

Keyword

nonn,base,easy

Author

Michel Lagneau, Aug 28 2013

Status

approved