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Index to OEIS: Section Tri

[ Aa | Ab | Al | Am | Ap | Ar | Ba | Be | Bi | Bl | Bo | Br | Ca | Ce | Ch | Cl | Coa | Coi | Com | Con | Cor | Cu | Cy | Da | De | Di | Do | Ea | Ed | El | Eu | Fa | Fe | Fi | Fo | Fu | Ga | Ge | Go | Gra | Gre | Ha | He | Ho | Ia | In | J | K | La | Lc | Li | Lo | Lu | M | Mag | Map | Mat | Me | Mo | Mu | N | Na | Ne | Ni | No | Nu | O | Pac | Par | Pas | Pea | Per | Ph | Poi | Pol | Pos | Pow | Pra | Pri | Pro | Ps | Qua | Que | Ra | Rea | Rel | Res | Ro | Ru | Sa | Se | Si | Sk | So | Sp | Sq | St | Su | Sw | Ta | Te | Th | To | Tra | Tri | Tu | U | V | Wa | We | Wi | X | Y | Z | 1 | 2 | 3 | 4 ]

tri-perfect numbers: A005820
triangle of x+y, etc.: see entries under: table of ...
triangle, coloring a: see coloring a triangle
triangle, filling a triangle with numbers: A003121, A064049, A064050
triangle: graphs by numbers of nodes and edges: A008406
Triangles, A006066, A006947, A007237
triangles, by perimeter: A005044*
triangular arrays of integers , see under: table (or triangle) of numbers
triangular arrays of integers, enumeration of special: A003402, A003403
triangular arrays, indexing: A073189*
triangular arrays, indexing: see T-coordinates for arrays
triangular lattice: see A2 lattice
triangular numbers, A000217*, A005448* (centered)
triangular numbers: number of ways of writing n as a sum of k triangular numbers, for k=1,...: A010054, A008441, A008443, A008438, A008439, A008440, A226252, A007331, A226253, A226254, A226255, A014787, A014809
triangular numbers, partitions into: A007294*
triangular numbers, sums of three: A002097, A053604
triangular numbers, sums of two: A051533*, A053603*, A051611
triangular square numbers: A001110*, A001109
triangular triples: A005044, A002620
triangulations (1): A000103 A000109 A000256 A001683 A002709 A002710 A002711 A002712 A002713 A003122 A003123 A003446
triangulations (2): A004305 A005495 A005497 A005498 A005499 A005500 A005501 A005502 A005503 A005504 A005505 A005506
triangulations (3): A005507 A005508 A005509 A005979 A006078 A006674 A007815 A011556 A019503 A019504 A027610 A028441
triangulations (4): A033961 A036572 A036573 A053440
tribonacci numbers: A000073 A000213 A001590 A003265 A056816 A081172 A145027 A001644
tribulations game, remoteness numbers: A006019
tribulations: A006019, A006020
tricapped prism: A005919, A005920
trigonometric functions which either increase or decrease monotonically: A004112, A016274, A046946, A046947, A046955, A046956, A046959,
trinomials over GF(2) , sequences related to :

trinomials over GF(2), irreducible: A001153 (Mersenne) A002475 A057460 A057461 A057463 A057474 A057476 A057477 A057478 A057479 A057480 A057481 A057482 A057486 A057646 A057774 A073571 A074710 A074743 A278572 A278573
trinomials over GF(2), primitive: A001153 (Mersenne), A073726, A073639, A074743, A074744

triperfect numbers: A005820
triple factorial numbers: A007661
triple-free sets of integers: A004059, A050291, A050292, A050294, A050296, A057561, A086316, A094708, A157244, A157245, A157271, A157282, A050293, A050295, A068060, A088808
triples of relatively prime numbers, sequences related to :

triples of relatively prime numbers: A071778*, A100448, A100450

triply perfect numbers: A005820
triprimes: see almost primes
trivalent graphs, see graphs, trivalent
truncatable primes sequences related to :

truncatable primes (1): A003459 A020994 A023107 A024770 A024785 A050986 A050987 A052023 A052024 A052025 A055521 A060825
truncatable primes (2): A076586 A076623 A078604 A085248 A085733 A086673 A086697 A094335 A101115 A103443 A103463 A103483
truncatable primes (3): A125590 A127698 A127889 A127890 A127891 A127892 A129669 A129670 A129671 A129672 A129673 A129692
truncatable primes (4): A129693 A129940 A129941 A129942 A129943 A129944 A129945 A132394 A133757 A133758 A137812 A144714

truncated polytopes, sequences related to :

truncated cube: A005911, A005912
truncated octahedron: A005910* A038170 A038171 A038180 A038181 A038386 A039741 A057112 A060135
truncated square numbers: A005892