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A049882 a(n) is the number of distinct sums of 4 different primes chosen from the first n primes. 3
1, 5, 13, 23, 32, 43, 57, 69, 84, 98, 110, 125, 139, 155, 170, 187, 202, 214, 230, 246, 262, 281, 299, 316, 330, 344, 357, 379, 401, 420, 437, 459, 477, 495, 515, 534, 553, 571, 586, 608, 627, 642, 657, 677, 701, 725, 748, 767, 783, 801, 821, 841, 859, 876, 900, 917, 935, 949, 970, 997 (list; graph; refs; listen; history; text; internal format)
OFFSET

4,2

LINKS

Table of n, a(n) for n=4..63.

EXAMPLE

From Petros Hadjicostas, Nov 19 2019: (Start)

The first 4 primes are 2, 3, 5, and 7 and they form only one sum, so a(4) = 1.

The first 5 primes are 2, 3, 5, 7, and 11, and they form 5 distinct sums each with four different terms (17, 21, 23, 25, 26), so a(2) = 5.

The first 6 primes are 2, 3, 5, 7, 11, and 13, and they form 13 distinct sums each with four different terms (17, 21, 23, 25, 26, 27, 28, 29, 31, 32, 33, 34, 36), so a(6) = 13. (End)

MAPLE

f := proc(n) local v, i, j, k, m;  v := {};

      if 4 <= n then

         for i from 1 to n - 3 do

         for j from i + 1 to n - 2 do

         for k from j + 1 to n - 1 do

         for m from k + 1 to n do

         v := v union {ithprime(i) + ithprime(j) + ithprime(k) + ithprime(m)};

         end do; end do; end do; end do;

      end if; nops(v); end proc;

seq(f(n), n=4..40); # Petros Hadjicostas, Nov 19 2019

CROSSREFS

Cf. A000040, A049880, A049881, A253250.

Sequence in context: A143988 A129806 A125830 * A108195 A074798 A031336

Adjacent sequences:  A049879 A049880 A049881 * A049883 A049884 A049885

KEYWORD

nonn

AUTHOR

Clark Kimberling

EXTENSIONS

Name edited by and more terms from Petros Hadjicostas, Nov 19 2019

STATUS

approved

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Last modified June 22 14:32 EDT 2021. Contains 345380 sequences. (Running on oeis4.)