Ulam sequence

E85412

The Ulam sequence is an integer sequence starting with 1 and 2 in which each subsequent term is the smallest integer that can be written uniquely as the sum of two distinct earlier terms.

All labels observed (1)

Label Occurrences
Ulam sequence canonical 1

How this entity was disambiguated

Statements (59)

Predicate Object
instanceOf integer sequence
mathematical sequence
definedByRecurrence Each subsequent term is the smallest integer that can be written uniquely as the sum of two distinct earlier terms
field number theory
firstFewTerms 1
102
106
11
114
128
13
131
138
139
148
155
156
16
166
177
18
180
189
2
26
28
3
36
38
4
47
48
53
57
6
62
69
71
78
8
81
85
97
99
hasFirstTerm 1
hasOEISID A002858
hasOpenProblems true
hasSecondTerm 2
hasSummandConstraint summands must be distinct earlier terms
hasUniquenessConstraint sum representation must be unique
isDeterministic true
isInfinite true
isNonPeriodic true
isStrictlyIncreasing true
namedAfter Stanislaw Ulam
surface form: Stanisław Ulam
requiresDistinctSummands true
requiresUniqueRepresentationAsSum true
startTermsFixed 1 and 2
usesOperation addition

How these facts were elicited

Referenced by (1)

Full triples — surface form annotated when it differs from this entity's canonical label.

Stanislaw Ulam notableWork Ulam sequence