A288820 Indices of records in A288818.

1, 2, 23, 223, 233, 237, 2237, 2337, 22337, 23137, 23337, 23373, 23797, 223373, 223797, 231373, 233137, 233797, 2233797, 2313797, 2331373, 2333797, 2337379, 2337397, 2353797, 22353797, 22373797, 23137397, 23173797, 23313797, 23353797, 23373797

Offset

1,2

Comments

If one assumes that larger terms begin with 22 or 23, then a(54)-a(64) are: 223373733797, 223537373797, 231337373797, 231353673797, 231353733797, 231373733797, 233137337397, 233537373797, 233753733797, 235313733797, and 235373733797. - Hans Havermann, Jul 31 2017

Links

Giovanni Resta, Table of n, a(n) for n = 1..53

Mathematica

ric[d_, lp_] := Block[{p, e, i, j, n = Length@d}, If[n == 0, cnt++, If[d[[1]] > 0, Do[p = FromDigits@ Take[d, i]; If[p > lp && PrimeQ@p, ric[Take[d, i - n], p]; Do[e = Take[d, {i + 1, j}]; If[e[[1]] > 0 && e != {1}, ric[Take[d, j - n], p]], {j, i+1, n}]], {i, n}]]]]; a[n_] := (cnt = 0; ric[ IntegerDigits@ n, 1]; cnt); L = {1}; k = 1; bst = 0; While[Length@L < 18, v = a[++k]; If[v > bst, AppendTo[L, k]; bst = v]]; L (* Giovanni Resta, Jun 19 2017 *)

Crossrefs

Cf. A288818, A288819 (records' value), A080670.

Sequence in context: A062600 A069590 A024028 * A340296 A242904 A068167

Adjacent sequences: A288817 A288818 A288819 * A288821 A288822 A288823

Keyword

nonn,base

Author

Hans Havermann, Jun 17 2017

Status

approved