This site is supported by donations to The OEIS Foundation.

# Index to OEIS: Section Ha

# Index to OEIS: Section Ha

- This is a section of the Index to the
**OEIS®**. - For further information see the main
**Index to OEIS**page. - Please read Index: Instructions For Updating Index to OEIS before making changes to this page.
- If you did not find what you were looking for in this Index, you can always search the database for a particular word or phrase.
- Full list of sections:

[ 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 ]

** h.c.p. (hexagonal close packing), sequences related to : **

- h.c.p., coordination sequence: A007899
- h.c.p., crystal ball sequence: A007202
- h.c.p., numbers represented by: A005870
- h.c.p., theta series of: A004012*, A005871, A005872, A005873, A005874, A005888, A005889, A005890
- h.c.p., walks on: A293237
- h.c.p.: see also A019298

** Hadamard matrices , etc., sequences related to : **

- Hadamard matrices, equivalence classes of: A007299, A036297 (equivalence classes under row/column permutation and negation); A096201 (equivalence classes under row/column permutation and negation, and transposition)
- Hadamard matrices, equivalent to transpose: A206704, A206705 (equivalence classes which contain the transpose)
- Hadamard matrices, excess of: A004118
- Hadamard matrices, largest automorphism group: A206707
- Hadamard matrices, mass of: A048615*/A048616*
- Hadamard matrices, number of: A007299*, A036297*, total number: A206711, A206712 (all Hadamard matrices regardless of equivalence)
- Hadamard matrices, orders of: A019442
- Hadamard matrices, regular: see A016742
- Hadamard matrices, 2-designs: A001111 (2-(4*n-1,2*n-1,n-1) symmetric designs)
- Hadamard matrices, 3-designs: A048885 (3-(4*n,2*n,n-1) designs, aka OA(4*n,4*n-1,2,2))
- Hadamard maximal determinant problem: A003432*, A003433, A036297, A051753
- Hadamard maximal determinant problem: see also determinants, maximal

half-totient function: A023022

Halving:: A003155, A006577

** Hamilton , sequences related to : **

- Hamilton cycles, paths, graphs: see graphs, Hamiltonian
- Hamilton numbers: A000905*, A002090, A006719
- Hamiltonian cycles: see graphs, Hamiltonian
- Hamiltonian graphs: see graphs, Hamiltonian
- Hamiltonian paths or cycles on the n-cube: see also Gray codes
- Hamiltonian paths: see graphs, Hamiltonian
- Hamiltonian polyhedra: see graphs, Hamiltonian

Hamming sequence: A051037

Hankel function: A002514

Hannah Rollman's numbers: A048992*

Hanoi, see Towers of Hanoi

happy factorizations: A007696, A007697, A007698

happy numbers: A007770*, A038497, A001273

happy numbers: see also A031177, A068571, A046519, A035502, A035503, A055629

Harary and Palmer, **Graphical Enumeration**, **sequences found in**

hard-hexagon model: A007236

** harmonic , sequences related to : **

- harmonic coefficients, triangle of: A027858
- harmonic means: (1) A001599, A001600, A006086, A006087, A007340, A046793, A046794, A046795, A046796, A046797, A053626, A053627
- harmonic means: (2) A053628, A053629, A055081, A056136
- harmonic numbers: A001599*, A001008*/A002805*, A035527
- harmonic numbers: see also A001600, A008380, A035047, A035048, A046024, A051046, A052488, A055573
- harmonic series (or sums): A002387*, A004080*
- harmonic series: see also A004796, A004980, A056053, A092135, A092318, A281355
- harmonic series, odd: A074599/A025547
- harmonic triangle of Leibniz: A003506*
- harmonic triangle of Leibniz: see also A002457, A007622, A046200, A046201, A046202, A046203, A046204, A046205, A046206, A046207, A046208, A046212

Harshad numbers: A005349*

Harvey Friedman's sequence: see A014221

Hauptmodul series: A007325

Havender tableaux: A007345

HCF (highest common factor) is written as GCD (greatest common divisor) in the OEIS

hcf (highest common factor) is written as GCD (greatest common divisor) in the OEIS

HCF: the canonical spelling in the OEIS is GCD (nor HCF or gcd) for "greatest common divisor"

hcf: the canonical spelling in the OEIS is GCD (nor hcf or gcd) for "greatest common divisor"

hcp: see h.c.p

- This is a section of the Index to the
**OEIS®**. - For further information see the main
**Index to OEIS**page. - Please read Index: Instructions For Updating Index to OEIS before making changes to this page.
- If you did not find what you were looking for in this Index, you can always search the database for a particular word or phrase.
- Full list of sections:

[ 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 ]