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A125902 a(n) = sum of the first n primes which are coprime to n. 1
2, 8, 14, 26, 36, 72, 70, 98, 126, 190, 186, 276, 268, 372, 432, 438, 484, 634, 620, 784, 864, 950, 940, 1156, 1156, 1356, 1368, 1584, 1564, 1978, 1820, 1986, 2262, 2408, 2572, 2742, 2710, 3066, 3250, 3440, 3406, 4016, 3788, 4214, 4430, 4636, 4614, 5112 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..48.

EXAMPLE

The first 6 primes which are coprime to 6 are 5,7,11,13,17,19. So a(6)=5+7+11+13+17+19 = 72.

MATHEMATICA

f[n_] := Block[{c = n, k = 0, p, s = 0}, While[c > 0, k++; While[p = Prime[k]; GCD[p, n] > 1, k++ ]; c--; s += p; ]; s]; Table[f[n], {n, 50}] (* Ray Chandler, Dec 14 2006 *)

CROSSREFS

Cf. A119993, A125903.

Sequence in context: A107072 A120413 A161156 * A295055 A277276 A324785

Adjacent sequences:  A125899 A125900 A125901 * A125903 A125904 A125905

KEYWORD

nonn

AUTHOR

Leroy Quet, Dec 13 2006

EXTENSIONS

Extended by Ray Chandler, Dec 14 2006

STATUS

approved

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Last modified August 11 04:03 EDT 2020. Contains 336421 sequences. (Running on oeis4.)