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 A267757 Number of terms of A072873 less than or equal to 10^n. 1
 2, 5, 9, 15, 25, 36, 52, 73, 98, 129, 167, 213, 270, 338, 421, 517, 632, 768, 920, 1102, 1311, 1547, 1824, 2143, 2501, 2911, 3379, 3906, 4493, 5164, 5920, 6757, 7704, 8765, 9943, 11247, 12706, 14324, 16103, 18078, 20268, 22666, 25315, 28239, 31437, 34941, 38785, 43002 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS A072873: Numbers n such that sum( e(i)/p(i) ) is an integer, where the prime factorization of n is prod ( p(i)^e(i) ). LINKS Robert G. Wilson v, Table of n, a(n) for n = 1..108 MATHEMATICA mx = 10^108; lst = Sort@ Flatten@ Table[ 2^a*3^b*5^c*7^d*11^e*13^f*17^g*19^h*23^i*29^j*31^k*37^l*41^m*43^n*47^o*53^p, {a, 0, Log[ 2, mx], 2}, {b, 0, Log[ 3, mx/ 2^a], 3}, {c, 0, Log[ 5, mx/(2^a*3^b)], 5}, {d, 0, Log[ 7, mx/(2^a*3^b*5^c)], 7}, {e, 0, Log[11, mx/(2^a*3^b*5^c*7^d)], 11}, {f, 0, Log[13, mx/(2^a*3^b*5^c*7^d*11^e)], 13}, {g, 0, Log[17, mx/(2^a*3^b*5^c*7^d*11^e*13^f)], 17}, {h, 0, Log[19, mx/(2^a*3^b*5^c*7^d*11^e*13^f*17^g)], 19}, {i, 0, Log[23, mx/(2^a*3^b*5^c*7^d*11^e*13^f*17^g*19^h)], 23}, {j, 0, Log[29, mx/(2^a*3^b*5^c*7^d*11^e*13^f*17^g*19^h*23^i)], 29}, {k, 0, Log[31, mx/(2^a*3^b*5^c*7^d*11^e*13^f*17^g*19^h*23^i*29^j)], 31}, {l, 0, Log[37, mx/(2^a*3^b*5^c*7^d*11^e*13^f*17^g*19^h*23^i*29^j*31^k)], 37}, {m, 0, Log[41, mx/(2^a*3^b*5^c*7^d*11^e*13^f*17^g*19^h*23^i*29^j*31^k*37^l)], 41}, {n, 0, Log[43, mx/ 2^a*3^b*5^c*7^d*11^e*13^f*17^g*19^h*23^i*29^j*31^k*37^l*41^m)], 43}, {o, 0, Log[47, mx/(2^a*3^b*5^c*7^d*11^e*13^f*17^g*19^h*23^i*29^j*31^k*37^l*41^m*43^n)], 47}, {p, 0, Log[53, mx/(2^a*3^b*5^c*7^d*11^e*13^f*17^g*19^h*23^i*29^j*31^k*37^l*41^m*43^n*47^o)], 53}, {q, 0, Log[59, mx/ 2^a*3^b*5^c*7^d*11^e*13^f*17^g*19^h*23^i*29^j*31^k*37^l*41^m*43^n*47^o*53^p)], 59}]; Table[ Length@ Select[lst, # <= 10^n &], {n, 108}] CROSSREFS Cf. A072873. Sequence in context: A134342 A100287 A007176 * A176691 A274355 A054253 Adjacent sequences:  A267754 A267755 A267756 * A267758 A267759 A267760 KEYWORD nonn AUTHOR Robert G. Wilson v, Jan 20 2016 STATUS approved

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Last modified February 20 12:57 EST 2019. Contains 320327 sequences. (Running on oeis4.)