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 A257524 Composite numbers equal to the sum of the prime factors, with multiplicity, of the next k numbers, for some k. 5
 49, 132, 1070, 1140, 2862, 40652, 158170, 204252, 365859, 656092, 806526, 812571, 861444, 1031941, 4017612, 4227164, 8045675, 15843252, 16298931, 48625784, 81869208, 129071545, 142516026, 219039320, 266299218, 520700301, 537506243, 590578292, 600500937, 915352703 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Values of k are 3, 4, 8, 5, 9, 9, 17, 25, 22, 18, 11, 15, 9, 20, 10, 12, 21, 26, 30, 25, 15, 14, 21, 30, 22, 26, 20, 13, 19, 11, ... LINKS EXAMPLE For 49, consider the prime factors of the next 3 numbers, 50, 51, 52: 2, 5, 5; 3, 17; 2, 2, 13. Their sum is 2 + 5 + 5 + 3 + 17 + 2 + 2 + 13 = 49. For 132, consider the prime factors of the next 4 numbers, 133, 134, 135, 136: 7, 19; 2, 67; 3, 3, 3, 5; 2, 2, 2, 17. Their sum is 7 + 19 + 2 + 67 + 3 + 3 + 3 + 5 + 2 + 2 + 2 + 17 = 132. MAPLE with(numtheory): P:= proc(q) local a, d, j, k, n; for n from 2 to q do if not isprime(n) then a:=0; k:=0; while a

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Last modified May 16 19:45 EDT 2021. Contains 343951 sequences. (Running on oeis4.)