A133605 - OEIS

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

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OFFSET

1,1

COMMENTS

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

LINKS

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

EXAMPLE

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.

PROG

(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

CROSSREFS

Cf. A011185, A005282, A133604.

Sequence in context: A020701 A024885 A180459 * A218607 A289916 A014252

Adjacent sequences: A133602 A133603 A133604 * A133606 A133607 A133608

KEYWORD

nonn

AUTHOR

Klaus Brockhaus, Sep 18 2007

STATUS

approved