13,576 reputation
11859
bio website go.helms-net.de
location Kassel, Germany
age 62
visits member for 4 years, 4 months
seen 2 hours ago

Mathematics is only a hobby - although I have done undergrad courses in the 70s. But part of my job was doing statistics and this kept me near my favourite subject "linear algebra" (programmed factor-analysis and a matrix-orientated calculator MatMate). Around 2002 I came in contact with the internet community in math newsgroups and could improve my Collatz discussion. Next subject was the Bernoulli numbers, then integer matrices and since 2006 the problem of iterated exponentiation aka tetration. Serving half-time jobs in teaching here at the university I found time to fiddle with that subjects in depth - and found love with the exploratory approach and impulse of the 18'th century numbertheory, namely L. Euler, "the master of us all"... Due to lack of formal education I've to do my "research" widely on my own - but that's what I just like: to find structure, pattern, laws from the ground.


Feb
18
reviewed Approve Logic puzzle: Which octopus is telling the truth?
Jan
26
reviewed Approve How to do optimization on expression which includes Reciprocal
Jan
23
reviewed Approve How to solve $(1+i\sqrt{3})^{-1+i}$??
Jan
23
reviewed Approve Calculate Laurent series for $1/ \sin(z)$
Jan
17
reviewed Approve Identification of legitimate distribution function
Jan
16
reviewed Approve Rainbow Hats Puzzle
Jan
12
reviewed Approve What is the integrating factor of $2xy'+x^{2}e^{1-x^2}y=2$
Dec
28
reviewed Approve Intuition, proof, one-sided group definition - Any set with Associativity, Left Identity, Left Inverse is a Group - Fraleigh p.49 4.38
Dec
27
reviewed Approve Dirac delta of nonlinear multivariable arguments
Dec
27
reviewed Approve Combination with at least two people.
Dec
27
reviewed Approve Finding polynomials sattisfying $P\bigr(-c + K/(u+c)\bigl) (u+c)^2/K =P(u)$
Dec
22
reviewed Approve Maclaurin expansion of arctan: convergence?
Dec
20
reviewed Approve What are the subgroups of $\mathbb{Z}_{5}^\ast \times \mathbb{Z}_{4}^\ast$? I think I count $5$ of them.
Dec
4
reviewed Approve Prove associativity (to prove semiring)
Dec
4
reviewed Approve calculus problem can you explain how to solve them?
Dec
4
reviewed Approve Calculus interval problem please explain how to solve it
Dec
4
reviewed Approve Minimum sample size to obtain population mean?
Dec
4
reviewed Approve Indeterminate Equations using kuttaka
Dec
4
reviewed Approve Compute for Cov(X,Y) and Correlation(X,Y)
Dec
4
reviewed Approve Prove or disprove the following proposition