A004202 -id:A004202 - cp's OEIS frontend

A253169 Smallest m such that A256188(m) = n.

1, 2, 9, 5, 6, 36, 10, 11, 12, 100, 17, 18, 19, 20, 225, 26, 27, 28, 29, 30, 441, 37, 38, 39, 40, 41, 42, 784, 50, 51, 52, 53, 54, 55, 56, 1296, 65, 66, 67, 68, 69, 70, 71, 72, 2025, 82, 83, 84, 85, 86, 87, 88, 89, 90, 3025, 101, 102, 103, 104, 105, 106, 107

Offset: 1

Reinhard Zumkeller, Mar 26 2015

nonn

A256188(a(n)) = n and A256188(m) != n for m < a(n).

Reinhard Zumkeller, Table of n, a(n) for n = 1..10000

Cf. A256188, A000537, A010054, A000290.

import Data.List (elemIndex); import Data.Maybe (fromJust)
a253169 = (+ 1) . fromJust . (`elemIndex` a256188_list)

a(n) = if n triangular then n^2 else A004202(n + 1 - A002024(n)).

A347350 Sequence obtained by writing the first 4 integers and skipping 1, then writing the next 5 integers and skipping 2, then writing the next 6 and skipping 3, etc.

Original entry on oeis.org

1, 2, 3, 4, 6, 7, 8, 9, 10, 13, 14, 15, 16, 17, 18, 22, 23, 24, 25, 26, 27, 28, 33, 34, 35, 36, 37, 38, 39, 40, 46, 47, 48, 49, 50, 51, 52, 53, 54, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 97, 98, 99, 100, 101, 102, 103, 104, 105

Offset: 1

Michel Marcus, Aug 28 2021

nonn

Ana Rechtman, Août 2021, 4e défi, Images des Mathématiques, CNRS, 2021.
Index entries for sequences generated by sieves

Cf. A004201, A004202, A048859.

lista(nn) = {my(va=[1..nn], list=List()); my(i=4, j=1, pos=1, ok=1); while (ok, for(m=1, i, if (pos > nn, ok=0, listput(list, va[pos])); pos++; ); pos += j; i++; j++;); Vec(list);}

cp's OEIS Frontend

A253169 Smallest m such that A256188(m) = n.

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