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A115333 Sum of primes that do not divide n and are less than the largest prime dividing n. 0
0, 0, 2, 0, 5, 0, 10, 0, 2, 3, 17, 0, 28, 8, 2, 0, 41, 0, 58, 3, 7, 15, 77, 0, 5, 26, 2, 8, 100, 0, 129, 0, 14, 39, 5, 0, 160, 56, 25, 3, 197, 5, 238, 15, 2, 75, 281, 0, 10, 3, 38, 26, 328, 0, 12, 8, 55, 98, 381, 0, 440, 127, 7, 0, 23, 12, 501, 39, 74, 3, 568, 0, 639, 158, 2, 56, 10 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,3

COMMENTS

When n is prime, n = largest prime dividing n; hence a(n) is the sum of all primes less than n = A034387(n)-n. a(n) = SUM{p such that p is in A000040 AND NOT(p|n) AND p < A006530(n)}. - Jonathan Vos Post, Mar 08 2006

The zeros give A055932: All prime divisors are consecutive primes starting at 2. - Robert G. Wilson v, May 01 2006

LINKS

Table of n, a(n) for n=1..77.

EXAMPLE

The primes < 7 and coprime to 7 are 2, 3 and 5. So a(7) = 2+3+5 = 10.

MATHEMATICA

f[n_] := Plus @@ Complement[Prime@ Range@ PrimePi[ Max[First /@ FactorInteger@n] - 1], First /@ FactorInteger@n]; Array[f, 77] (* Hans Havermann, Mar 06 2006 *)

CROSSREFS

Cf. A000040, A006530, A034387, A066911, A083720.

Sequence in context: A078153 A104035 A196409 * A242689 A242688 A242687

Adjacent sequences:  A115330 A115331 A115332 * A115334 A115335 A115336

KEYWORD

nonn

AUTHOR

Leroy Quet, Mar 05 2006

EXTENSIONS

More terms from Hans Havermann, Mar 06 2006

STATUS

approved

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Last modified June 17 04:26 EDT 2019. Contains 324183 sequences. (Running on oeis4.)