Direct Proof Of Theorem Research Articles

On the Keller limit and generalization

Let c be any real number and let $$u_{n}(c)=(n+1) \biggl(1+\frac{1}{n+c} \biggr)^{n+c}-n \biggl(1+\frac {1}{n+c-1} \biggr)^{n+c-1}-e. $$ In this note, we establish an integral expression of $u_{n}(c)$ , which provides a direct proof of Theorem 1 in (Mortici and Jang in Filomat 7:1535-1539, 2015).

The Multiple Gamma-Functions and the Log-Gamma Integrals

In this paper, which is a companion paper to [W], starting from the Euler integral which appears in a generalization of Jensen’s formula, we shall give a closed form for the integral of log . This enables us to locate the genesis of two new functions and considered by Srivastava and Choi. We consider the closely related functionA(a)and the Hurwitz zeta function, which render the task easier than working with the functions themselves. We shall also give a direct proof of Theorem 4.1, which is a consequence of [CKK, Corollary 1.1], though.

A direct proof of theorem on generalized Jordan form of linear operators

The present paper gives a direct proof of the following result: for any linear operator over arbitrary field there exists a basis in which it has a polyquasicyclic matrix, i.e. a generalized Jordan form of second kind. The polyquasicyclic form of a linear operator is uniquely determined up to the order of direct summands on the diagonal, and it is shown that the generalized Jordan form of second kind is a link that connects the classical Jordan form and the rational canonical form.

A New Identity for (q;q) 10 with an Application to Ramanujan's Partition Congruence Modulo 11

Our principal second goal is to show that this identity leads to a short proof of Ramanujan’s famous congruence p(11n+6) ≡ 0 (mod 11), where p(n) denotes the number of unrestricted partitions of the positive integer n. Our proof of Theorem 2.2 is short but depends upon some results of Ramanujan from his notebooks [18]. In Section 4, we give a more elementary proof, based upon Ramanujan’s 1ψ1 summation formula, of Ramanujan’s principal result, Lemma 2.1, which is employed in our proof of Theorem 2.2. In Section 5, we give an entirely different and direct proof of Theorem 2.2 based on several elementary identities for theta functions due to Ramanujan. In fact, during our first proof of Theorem 2.2, we establish a special case of a general result on Eisenstein series found in Ramanujan’s lost notebook [19, p. 369]. More precisely, Ramanujan asserts that every member of a certain class of infinite series can be expressed in terms of Ramanujan’s Eisenstein series P , Q, and R (to be defined in Section 6). A less precise version of this claim appears in Ramanujan’s notebooks [18], [2, p. 65, Entry 35(i)], but we prove the better version in Section 6. D. Stanton empirically discovered an analogue of Theorem 2.2, and in Section 7 we give a proof of Stanton’s identity. In Section 8, we prove that (q; q) ∞ is lacunary; in this connection, see a result of J.–P. Serre [20].

ImbeddingC1intoH1

AbstractThis article gives a direct proof of Theorem 7.58 of Greiner [4]. This result implies that the classical Mikhlin-Calderón-Zygmund calculus for the principal value convolution operators on ℂ is, in a natural way, the limit of the Laguerre calculus for principal value convolution operators on ℍ1= ℂ x ℝ.

Growth conditions on powers of Hermitian elements

Roe (7) has recently given a striking characterization of the sine function as essentially the only function defined on the real line which has all its derivatives and successive ‘integrals’ bounded by a uniform bound, and this result has since been generalized by Burkill (5). In this note we relate this work to Banach algebra theory in a natural way by demonstrating the equivalence of Theorems 1 and 2 below, and also by giving a direct proof of Theorem 1. (Theorem 2 is Burkill's generalization of Roe's result stated in complex form.) We enunciate a Banach space version of the result (Theorem 3), and a further generalization of all these results is given in Theorem 4.

Ferrers digraphs and threshold graphs

We deduce a set of known characterizations of threshold graphs (Theorem 3) from a set of characterizations of Ferrers digraphs (Theorem 1) by investigating the connection between symmetric Ferrers digraphs and threshold graphs. A direct proof of Theorem 3 is easier than the one provided in here, but the purpose of this paper is to view Theorem 1 as an extension of Theorem 3 to the directed case (this extension point of view still holds on an algorithmic ground).