OFFSET
1,1
REFERENCES
N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).
LINKS
Reinhard Zumkeller, Table of n, a(n) for n = 1..10000
CNRS press release, Sum of Digits of Prime Numbers Is Evenly Distributed: New Mathematical Proof of Hypothesis
Christian Mauduit and Joël Rivat, Sur un problème de Gelfond: la somme des chiffres des nombres premiers (French) [On a problem posed by Gelfond: the sum of digits of primes] Ann. of Math. (2) 171(2010), no. 3, 1591--1646. MR2680394 (2011j:11137)
R. G. Wilson, V, Letter to C. A. Pickover, Mar. 1993
MAPLE
map(t -> convert(convert(t, base, 10), `+`), select(isprime, [2, (2*i+1 $ i=1..1000)])); # Robert Israel, Aug 16 2015
MATHEMATICA
Table[Apply[Plus, RealDigits[Prime[n]][[1]]], {n, 1, 100}]
Plus@@ IntegerDigits[Prime[Range[100]]] (* Zak Seidov *)
PROG
(Magma) [ &+Intseq(NthPrime(n), 10): n in [1..80] ]; // Klaus Brockhaus, Jun 13 2009
(PARI) dsum(n)=my(s); while(n, s+=n%10; n\=10); s
forprime(p=2, 1e3, print1(dsum(p)", ")) \\ Charles R Greathouse IV, Jul 15 2011
(PARI) a(n) = sumdigits(prime(n)); \\ Michel Marcus, Dec 20 2017
(Haskell)
a007605_list = map a007953 a000040_list -- Reinhard Zumkeller, Aug 04 2011
(Python)
from sympy import prime
def a(n): return sum(map(int, str(prime(n))))
print([a(n) for n in range(1, 80)]) # Michael S. Branicky, Feb 03 2021
CROSSREFS
KEYWORD
nonn,base,easy
STATUS
approved