A037282 Scan n from left to right once, erasing any primes.

1, 0, 0, 4, 0, 6, 0, 8, 9, 10, 0, 1, 0, 14, 1, 16, 0, 18, 0, 0, 1, 0, 0, 4, 0, 6, 0, 8, 0, 0, 0, 0, 0, 4, 0, 6, 0, 8, 9, 40, 0, 4, 0, 44, 4, 46, 0, 48, 49, 0, 1, 0, 0, 4, 0, 6, 0, 8, 0, 60, 0, 6, 6, 64, 6, 66, 0, 68, 69, 0, 0, 0, 0, 4, 0, 6, 0, 8, 0, 80, 81, 8, 0, 84, 8, 86, 8, 88, 0, 90, 91, 9, 9, 94, 9

Offset

1,4

Links

Table of n, a(n) for n=1..95.

Example

a(7) = a(77) = 0, a(1294) = 14.

Maple

catDigs := proc(L, i, j) local k ; add(L[k]*10^(k-i), k=i..j) ; end: A037282 := proc(n) local L, w, i, lenL, a ; L := convert(n, base, 10) ; lenL := nops(L) ; for w from lenL to 1 by -1 do for i from lenL-w+1 to 1 by -1 do a := catDigs(L, i, i+w-1) ; if isprime(a) then a := catDigs(L, 1, i-1)+10^(i-1)*catDigs(L, i+w, lenL) ; RETURN(A037282(a)) ; fi ; od: od: RETURN(n) ; end: seq(A037282(n), n=1..150) ; # R. J. Mathar, Oct 12 2007

Crossrefs

Sequence in context: A055672 A327964 A085562 * A191558 A075083 A179939

Adjacent sequences: A037279 A037280 A037281 * A037283 A037284 A037285

Keyword

nonn,base,easy

Author

N. J. A. Sloane

Extensions

More terms from R. J. Mathar, Oct 12 2007

Status

approved