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# User:Gerhard Kirchner

Teacher of mathematics and physics at a German high school (Gymnasium). Status: retired

My contributions to OEIS:

Aug.2016: Extension and theory for sequences A160375 and A110713

Oct.2016: Formula and proof for sequence A007495

Dec.2016: Aspects of prime multiplets in A086140

Dec.2016: New sequences A279765 and A280201

Jan.2017: Formula and proof for sequence A032434

Jan.2017: Application (gear wheels) for sequence A109340

Jan.2017: Recurrence and explicit formula for sequence A187243 with derivation of formulas

Feb.2017: Formula for sequence A000008

Feb.2017: Comment on sequence A002464

Feb.2017: Comment on sequence A000212

Feb.2017: Formula for sequence A001299

Mar.2017: New sequence (symmetric arrangements of non-attacking kings) A283184

Apr.2017: New application and formula for sequence A101481

Nov. 2017: Formula concerning number walls A295928

Dec.2017: General formula for Frobenius numbers A296307

Nov.2019: New sequence (number of subsets) A329146

Jan.2020: New sequences (best approximation) A331101 and A331115

Jan.2020: Formula (cont. fractions p<3) for sequence A320773

Apr.2020: Cont. fractions with constant terms A331960

Apr.2020: Cont. fractions with same pattern A334116

May 2020: Comment "Harmonic sequence" on A078141

July 2020: Points on a spiral A335298

July 2020: Fixed-point-free variations A336246

July 2020: New formula for the odd harmonic sequence and corrections in A092315 and several similar sequences

Sep. 2020: Generalized aspects of the harmonic sequence, new

Nov. 2020: Camel and banana problem based on the odd harmonic sequence

Dec. 2020: Number of convex polygons on a triangular grid.

Feb. 2022: Prime multiplets A350541, A350542, A350543

Feb. 2022: Tiling with right trominos, A351322-24

Mar 2022: Tiling with 2X2 tiles and dominos, A352431-33

Mar. 2022: Tiling with 2X2 and 1X1 tiles and dominos, A352589-91

May 2022: Tiling with 2X2 and 1X1 tiles and trominos, A353963-65

May 2022: Tiling with 1X1 tiles, dominos and trominos, A353877-79

May 2022: Tiling with 2X2 and 1X1 tiles, dominos and trominos, A353963-65

May 2022: Tiling with 2X2 tiles, dominos and trominos, A354010-12

Aug. 2022: Coloring a 3Xn grid A355881-83

Oct. 2022: Half area of convex polygons A357575-77

Dec. 2022: Area of a triangle enclosing a circle A358465

Dec. 2022: Area of a triangle enclosed by a circle A358681

Jan. 2023: 3-dimensional tilings of a 2 X 2 X n box A359884-86

Feb. 2023: More 3-dimensional tilings of a 2 X 2 X n box A360064-66