Volume 12, Issue 3 Hadi Roopaei D. Foroutannia The norm of backward difference operator Δ Downloads Abstract PDF Full article PDF DOI { copied = true; setTimeout(() => copied = false, 2000) })" :aria-label="copied ? 'DOI copied' : 'Copy DOI'" :title="copied ? 'Copied' : 'Copy DOI'" > Find all available articles from these authors Hadi Roopaei D. Foroutannia Find more articles with the same keywords matrix operator backward difference operator norm Cesàro matrix Hilbert matrix sequence space Find more articles with the same subject classes 26D15 40C05 40G05 47B37 47B39