A320719 Indices of primes followed by a gap (distance to next larger prime) of 42.

1879, 3732, 4059, 4135, 4714, 5355, 5948, 6160, 6841, 7434, 7724, 7746, 7952, 7980, 8081, 8269, 8580, 9303, 9395, 9971, 10045, 10305, 10968, 11023, 11135, 11251, 11338, 11399, 11515, 11807, 11888, 11901, 12089, 12374, 12488, 13277, 13447, 14497, 14802, 15086, 15089, 15350, 15612, 15785

Offset

1,1

Comments

Indices of the primes listed in A134120.

Links

Harvey P. Dale, Table of n, a(n) for n = 1..3000

Index entries for primes, gaps between.

Formula

a(n) = A000720(A134120(n)).

Mathematica

Position[Differences[Prime[Range[16000]]], 42]//Flatten (* Harvey P. Dale, Feb 22 2020 *)

Prog

(PARI) A(N=100, g=42, p=2, i=primepi(p)-1, L=List())={forprime(q=1+p, , i++; if(p+g==p=q, listput(L, i); N--||break)); Vec(L)} \\ returns the list of first N terms of the sequence

Crossrefs

Cf. A029707, A029709 (analog for gaps 2 & 4), A320701, A320702, ... A320720 (analog for gaps 6, 8, ..., 44), A116493 (gap 70), A116496 (gap 100), A116497 (gap 200), A116495 (gap 210).

Equals A000720 o A134120.

Indices of 42's in A001223.

Row 21 of A174349.

Sequence in context: A237570 A045201 A020407 * A358147 A235193 A072494

Adjacent sequences: A320716 A320717 A320718 * A320720 A320721 A320722

Keyword

nonn

Author

M. F. Hasler, Oct 19 2018

Status

approved