A133605 Elements of A011185 that are also the sum of a pair of distinct elements of A011185.

3, 5, 8, 13, 21, 74, 95, 182, 212, 413, 862, 1060, 1435, 1934, 4447, 5323, 7588, 19934, 23725, 24970, 29558, 43344, 45425, 48622, 55240, 63835, 91336, 98178, 177387, 180356, 206088, 333837, 400924, 418503, 429115, 598604, 776150, 990510, 993089

Offset: 1

Author

Klaus Brockhaus, Sep 18 2007

Keywords

• nonn

Comments

A011185 is the sequence of smallest numbers such that the pairwise sums of distinct elements are all distinct.

Examples

			A011185(1) = 1, A011185(2) = 2. 1 + 2 = 3 = A011185(3), hence 3 is in the sequence.
A011185(16) = 212, A011185(35) = 1722. 212 + 1722 = 1934 = A011185(37), hence 1934 is in the sequence.
		

Links

• Klaus Brockhaus, Table of n, a(n) for n = 1..75

Crossrefs

Cf. A011185, A005282, A133604.

Programs

Python

from itertools import count, islice
def A133605_gen(): # generator of terms
    aset2, alist = set(), []
    for k in count(1):
        bset2 = set()
        for a in alist:
            if (b:=a+k) in aset2:
                break
            bset2.add(b)
        else:
            if k in aset2:
                yield k
            alist.append(k)
            aset2.update(bset2)
A133605_list = list(islice(A133605_gen(),30)) # Chai Wah Wu, Sep 11 2023