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A380192
Sum mod(10) of digits of n-th prime.
2
2, 3, 5, 7, 2, 4, 8, 0, 5, 1, 4, 0, 5, 7, 1, 8, 4, 7, 3, 8, 0, 6, 1, 7, 6, 2, 4, 8, 0, 5, 0, 5, 1, 3, 4, 7, 3, 0, 4, 1, 7, 0, 1, 3, 7, 9, 4, 7, 1, 3, 8, 4, 7, 8, 4, 1, 7, 0, 6, 1, 3, 4, 0, 5, 7, 1, 7, 3, 4, 6, 1, 7, 6, 3, 9, 4, 0, 9, 5, 3, 4, 7, 8, 0, 6, 1, 7, 6, 1, 3, 7, 0, 9
OFFSET
1,1
COMMENTS
All remainders 0,...,9 occur in this sequence.
FORMULA
a(n) = A010879(A007605(n)).
MATHEMATICA
Mod[DigitSum[Prime[Range[100]]], 10] (* Paolo Xausa, Feb 06 2025 *)
PROG
(PARI) a(n) = sumdigits(prime(n)) % 10; \\ Michel Marcus, Jan 16 2025
CROSSREFS
KEYWORD
nonn,base
AUTHOR
Enrique Navarrete, Jan 15 2025
STATUS
approved