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 A046380 Palindromes with exactly 6 palindromic prime factors (counted with multiplicity). 1
 2772, 6776, 25452, 59895, 88788, 549945, 1931391, 8117118, 8447448, 51033015, 52711725, 58344385, 103838301, 535707535, 620434026, 1663223661, 8262112628, 15271417251, 25227972252, 27747974772, 27974547972, 92628082629, 97079897079, 6421339331246, 8401825281048 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 LINKS Chai Wah Wu, Table of n, a(n) for n = 1..49 PROG (Python) from sympy import factorint def palQgen10(l): # generator of palindromes in base 10 of length <= 2*l ....if l > 0: ........yield 0 ........for x in range(1, l+1): ............for y in range(10**(x-1), 10**x): ................s = str(y) ................yield int(s+s[-2::-1]) ............for y in range(10**(x-1), 10**x): ................s = str(y) ................yield int(s+s[::-1]) A046380_list = [] for x in palQgen10(6): ....a = factorint(x) ....if sum(list(a.values())) == 6: ........for p in a: ............s = str(p) ............if s != s[::-1]: ................break ........else: ............A046380_list.append(x) # Chai Wah Wu, Dec 26 2014 CROSSREFS Cf. A046332. Sequence in context: A205418 A231709 A046332 * A249228 A154081 A099691 Adjacent sequences:  A046377 A046378 A046379 * A046381 A046382 A046383 KEYWORD nonn,more,base AUTHOR Patrick De Geest, Jun 15 1998 EXTENSIONS a(19)-a(25) from Chai Wah Wu, Dec 26 2014 STATUS approved

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Last modified September 23 23:21 EDT 2018. Contains 315306 sequences. (Running on oeis4.)