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 A268605 a(1) = 0; a(n+1) is the smallest integer in which the difference between its digits sum and the a(n) digits sum is equal to the n-th prime. 2
 0, 2, 5, 19, 89, 1999, 59999, 4999999, 599999999, 199999999999, 399999999999999, 799999999999999999, 8999999999999999999999, 499999999999999999999999999, 29999999999999999999999999999999, 4999999999999999999999999999999999999 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS First 8 terms are primes (and are also in A061248). Next terms are not always primes. LINKS Francesco Di Matteo, Table of n, a(n) for n = 1..25 FORMULA a(n) = A051885( A007504(n-1) ).-  R. J. Mathar, Jun 19 2021 EXAMPLE a(4) = 19 and 1 + 9 = 10; so a(5) = 89 because 8 + 9 = 17 and 17 - 10 = 7, that is the 4th prime. PROG (Python) sumprime = 0 isPrime=lambda x: all(x % i != 0 for i in range(int(x**0.5)+1)[2:]) for i in range(2, 100): ..if isPrime(i): ....alfa = "" ....k = i + sumprime ....sumprime = k ....while k > 9: ......alfa = alfa + "9" ......k = k - 9 ....alfa = str(k)+alfa ....print alfa (PARI) findnext(x, k) = {sx = sumdigits(x); pk = prime(k); y = 1; while (sumdigits(y) - sx != pk, y++); y; } lista(nn) = {print1(x = 0, ", "); for (k=1, nn, y = findnext(x, k); print1(y, ", "); x = y; ); } \\ Michel Marcus, Feb 19 2016 CROSSREFS Cf. A269306, A061248, A067180, A051885. Sequence in context: A316700 A124348 A323389 * A205804 A052324 A020115 Adjacent sequences:  A268602 A268603 A268604 * A268606 A268607 A268608 KEYWORD nonn,base AUTHOR Francesco Di Matteo, Feb 17 2016 EXTENSIONS NAME adapted to offset. - R. J. Mathar, Jun 19 2021 STATUS approved

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Last modified September 20 05:37 EDT 2021. Contains 347577 sequences. (Running on oeis4.)