A347112 a(n) = concat(prime(n+1),n) mod prime(n).

1, 1, 3, 2, 3, 7, 10, 10, 0, 7, 22, 5, 8, 27, 4, 33, 40, 8, 17, 7, 37, 27, 42, 23, 37, 24, 15, 14, 102, 74, 50, 108, 96, 61, 86, 32, 9, 112, 138, 121, 62, 137, 52, 58, 48, 52, 192, 2, 22, 221, 185, 13, 89, 152, 141, 130, 257, 116, 182, 260, 212, 290, 156, 264

Offset

1,3

Links

Table of n, a(n) for n=1..64.

Simon Strandgaard, Plot of 10000 terms

Example

a(1) = concat( 3,1) mod  2 = 1,
a(2) = concat( 5,2) mod  3 = 1,
a(3) = concat( 7,3) mod  5 = 3,
a(4) = concat(11,4) mod  7 = 2,
a(5) = concat(13,5) mod 11 = 3.

Mathematica

Array[Mod[#3*10^(1 + Floor[Log10[#1]]) + #1, #2] & @@ {#, Prime[#], Prime[# + 1]} &, 64] (* Michael De Vlieger, Aug 18 2021 *)

Prog

(PARI) a(n) = eval(Str(prime(n+1), n)) % prime(n);
(Ruby) require 'prime'
values = []
primes = Prime.first(50)
primes.each_index do |n|
  next if n < 1
  values << (primes[n].to_s + n.to_s).to_i % primes[n-1]
end
p values
(Python)
from sympy import prime
def a(n): return int(str(prime(n+1)) + str(n))%prime(n)
print([a(n) for n in range(1, 65)]) # Michael S. Branicky, Aug 18 2021

Crossrefs

Cf. A000040, A075110.

Sequence in context: A215934 A323895 A274508 * A227104 A171721 A225695

Adjacent sequences: A347109 A347110 A347111 * A347113 A347114 A347115

Keyword

nonn,base

Author

Simon Strandgaard, Aug 18 2021

Status

approved