Molecular spectra observed toward K4-47 identified with the IRAM 30 m (2 mm) and ARO telescopes (1 and 3 mm). The spectral resolution is 2 MHz. Left panel, in descending order: (a), (b) J = 3 → 2 (130.2687 GHz) and J = 4 → 3 (173.6882 GHz) transitions of SiO; (c), (d) JKa,Kc = 20,2 → 10,1 (127.8568 GHz) and JKa,Kc = 21,1 → 20,2 (172.2671 GHz) transitions of H2CNH, with a blend of the J = 19 → 18 lines of HCC13CN and HC13CCN (172.1327 GHz and 172.116 GHz, respectively); (e) J = 9 → 8 line of CH3CCH, consisting of blended K = 0 and 1 components (average frequency of K = 0 and 1 components: 153.8158 GHz; see Table 1), as well as its ﹩{{\mathrm{CH}}_{3}}^{13}﹩CCH isotopologues (average frequency: 153.7519 GHz) and the JKa,Kc = 32,2 → 21,1 transition of c-CC13CH2 (153.8946 GHz); and (f) J = 1 → 0 line of N2H+ (93.1734 GHz). Right panel, in descending order: (g) JKa,Kc = 41,4 → 30,3 (150.8519 GHz) and JKa,Kc = 40,4 → 31,3 (150.8207 GHz) transitions of c-C3H2, (h) JKa,Kc = 21,1 → 11,0 line of H2CO (150.4983 GHz) and (i) JKa,Kc = 21,2 → 11,1 transition of ﹩{{{\rm{H}}}_{2}}^{13}﹩CO (137.450 GHz); (j) J = 7 → 6 lines of CH3CN and ﹩{{\mathrm{CH}}_{3}}^{13}﹩CN (K = 0 and 1, blended; average frequencies: 128.7782 GHz and 128.7144 GHz, respectively); (k) J = 18 → 17 transitions of H13C13CCN and H13CC13CN (158.1058 GHz and 157.9845 GHz, respectively), and (l) fine/hyperfine components of the N = 2 → 1 transition of CN, centered at 226.7684 GHz; fine structure splitting is shown under the spectrum (see Table 1). H2CNH, CH3CCH, CH3CN, and all 13C-substituted species are new detections for PNe.