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A354975
a(n) = Sum_{i=1..n} (prime(i+n) mod prime(i)).
3
1, 2, 6, 9, 16, 26, 25, 46, 47, 54, 81, 112, 140, 116, 173, 215, 254, 234, 317, 329, 409, 440, 511, 584, 581, 582, 666, 649, 776, 866, 875, 967, 1057, 1152, 1310, 1419, 1246, 1294, 1296, 1551, 1599, 1722, 1970, 2152, 2166, 2154, 2338, 2396, 2523, 2831, 3120, 2867, 3220, 3332, 3274, 3266, 3462
OFFSET
1,2
LINKS
EXAMPLE
For n = 3, a(n) = (7 mod 2) + (11 mod 3) + (13 mod 5) = 1+2+3 = 6.
MAPLE
f:= proc(n) local k;
add(ithprime(n+k) mod ithprime(k), k=1..n)
end proc:
map(f, [$1..100]);
MATHEMATICA
a[n_]:=Sum[Mod[Prime[i+n], Prime[i]], {i, n}]; Array[a, 57] (* Stefano Spezia, Jun 15 2022 *)
PROG
(PARI) a(n) = sum(i=1, n, prime(i+n) % prime(i)); \\ Michel Marcus, Jun 15 2022
(Python)
from sympy import prime
def A354975(n): return sum(prime(i+n) % prime(i) for i in range(1, n+1)) # Chai Wah Wu, Jun 19 2022
CROSSREFS
KEYWORD
nonn
AUTHOR
J. M. Bergot and Robert Israel, Jun 15 2022
STATUS
approved